China has overtaken Japan as the world's second-biggest economy.

Japan's economy was worth $5.474 trillion (£3.414 trillion) at the end of 2010, figures from Tokyo have shown. China's economy was closer to $5.8 trillion in the same period.

Japan has been hit by a drop in exports and consumer demand, while China has enjoyed a manufacturing boom.

At its current rate of growth, analysts see China replacing the US as the world's top economy in about a decade.

Two security guards and an insurgent were killed in an attack in the Afghan capital Kabul, officials say.

Reports said the blast occurred just inside a shopping complex in the city centre after an attacker carrying explosives was challenged by guards.

A gun battle which broke out following the explosion has now ended.

It is the second attack in less than three weeks in the heavily fortified Afghan capital, after nine died in an attack on a supermarket on 28 January.

The Taliban told the BBC they had carried out that attack.

Monday's attack is thought to have begun when an attacker was challenged by security guards as he attempted to gain access to the shopping precinct, says the BBC's Quentin Sommerville in Kabul.

When Washington's red-walled Opera House drew in friends and fellow travellers from the world over to pay tribute last week to veteran American diplomat Richard Holbrooke, President Barack Obama set them a challenge.

"He made a difference. Let us now carry that work forward in our time," Mr Obama declared as he ended his eulogy for the Special Representative for Afghanistan and Pakistan, following his sudden death of a heart attack last month.

But who would fill this larger-than-life figure's big dusty boots?

Names mentioned by several people close to this process are obvious choices on Washington's rollcall of the best and brightest.

But many tried-and-tested troubleshooters are said to be demurring, citing other commitments, advancing age, or the daunting scale of the task.

How will the approaches championed by Mr Holbrooke move forward, including a strong civilian role alongside the growing military juggernaut and its powerful four-star, all-star General David Petraeus?

"The essence of the challenge is getting the balance right between the military and the political, civilian and diplomatic aspects," reflected former deputy Secretary of State Strobe Talbott, a close friend of Mr Holbrooke, who now heads the Brookings Institution.

"That's a 21st Century ass-whooping right there," says a US marine as an airstrike turns a mud compound into dust. That was the offensive against the Taliban in Marjah, in southern Afghanistan, in the spring. The video, filled with a constant chatter of automatic fire, was taken by marines and passed to us.

After a year-long campaign of "ass-whooping", Nato hopes it has "shaped the battlefield" to help achieve its objectives for the next phase of the campaign. The plan is to leave the Taliban weakened enough for the Afghan police and army to start taking over from the international forces. Another aim may be to force the insurgents into talks with the government, though this is not publicly stated by Nato officers.

"Finally, we've aligned our resources with the demands of the campaign," said Nato's top civilian official in Afghanistan, Mark Sedwill, speaking about the surge of forces ordered by President Obama. "It's still fragile. There's a long campaign ahead but we've regained the initiative having, candidly, lost it in the past."

Recent years have seen the re-emergence of the hardline Islamic Taliban movement as a fighting force in Afghanistan and a major threat to its government.

They are also threatening to destabilise Pakistan, where they control areas in the north-west and are blamed for a wave of suicide bombings and other attacks.

The Taliban emerged in the early 1990s in northern Pakistan following the withdrawal of Soviet troops from Afghanistan.

A predominantly Pashtun movement, the Taliban came to prominence in Afghanistan in the autumn of 1994.

It is commonly believed that they first appeared in religious seminaries - mostly paid for by money from Saudi Arabia - which preached a hard line form of Sunni Islam.

The Taliban's promise - in Pashtun areas straddling Pakistan and Afghanistan - was to restore peace and security and enforce their own austere version of Sharia, or Islamic law, once in power.

A major international conference on Afghanistan has backed President Hamid Karzai's timetable for control of security to be transferred from foreign to Afghan forces by 2014. The BBC's Ian Pannell in Kabul looks at the chances of meeting that goal.

By most estimates the security situation across the country looks increasingly bad.

Violence continues to rise and June was the deadliest month in nearly nine years of war.

According to the UN, the number of roadside bombings rose by nearly 100% in the first quarter of this year compared with 2009.

Assassinations rose by half and suicide attacks doubled. More than 1,000 people died in the first six months of the year, with June being the worst so far for foreign troops.

But military commanders and the politicians who gathered in Kabul on Tuesday think they are on the right track.

Their argument is that the rise in violence is an expected but temporary result of a surge in troops that has deliberately and sometimes aggressively targeted the Taliban in their havens.

As a powerful governor is gunned down in broad daylight in Islamabad amid a major political crisis, guest columnist Ahmed Rashid says Pakistan faces a bumpy ride this year.

To paraphrase Shakespeare, when crises come to Pakistan they come not as single spies but in battalions.

Among them is a burgeoning economic crisis with massive price increases and severe gas, electricity and fuel shortages, 15% inflation and the stoppage of a vital International Monetary Fund (IMF) loan.

There is unprecedented pressure on Islamabad from the US and Nato to eliminate extremists, with alleged terrorism plots linked to Pakistani militants foiled recently in Denmark and other European countries.

Also, the country's Islamic parties are attempting to mobilise the public to block proposed reforms to controversial blasphemy laws.

Days into the new year, Punjab province's Governor Salman Taseer - who had spoken out against those laws - was shot dead in the Pakistani capital Islamabad.

India's main opposition party has criticised Foreign Minister SM Krishna for reading out the speech of the Portuguese foreign minister at the UN.

Mr Krishna had no "moral right" to continue after he brought "shame" to India, senior Bharatiya Janata Party (BJP) leader Venkaiah Naidu said.

Mr Krishna read out the wrong speech on Saturday for about three minutes before being corrected by an official.

Later, he said it was "a mistake" and that there was "nothing wrong in it".

Explaining the blunder, Mr Krishna said these things happen because many of these speeches make the same initial points.

Missile attacks by US drones in Pakistan's tribal areas have more than doubled under the Obama administration, research by the BBC Urdu service shows.

Since January 2009 nearly 2,500 people have been killed in Pakistan as a result of US drones and Islamic militant attacks. The graphics below show how Islamic militant strongholds in the border area close to Afghanistan have been targeted by US drone aircraft, while, at the same time, Islamic militants have carried out attacks across Pakistan.

Missile attacks by US drones in Pakistan's tribal areas have more than doubled under the Obama administration, research by the BBC Urdu service shows.

Compared with 25 drone strikes between January 2008 and January 2009, there were at least 87 such attacks between President Obama taking office on 20 January 2009 and the end of June 2010.

More than 700 people have been killed in such attacks under Mr Obama, compared with slightly fewer than 200 from under his predecessor, George W Bush.

The militant backlash over the same period has been even more violent. Extremists have struck more than 140 times in various Pakistani locations, killing more than 1,700 people and injuring hundreds more, the BBC research shows.

Afghan troop map: US and Nato deployments

The US is the largest contributing nation to the international forces in Afghanistan whose numbers now total, more than 140,000.

The US has around 90,000 troops deployed with the Nato-ledInternational Security Assistance Force (Isaf) in Afghanistan with an additional 10,000 deployed as part of the US Operation Enduring Freedom, mainly in the East regional command.

The Afghan-Pakistan border region is widely believed to be the front line in the war against Islamic militants. see how militants operate on either side of the border.

Helmand, Chaghai

Kabul's writ has never run strong in the remote southern plains of Helmand province. For this reason, it has emerged as the most significant Taliban stronghold in Afghanistan. Further south, across the border in Pakistan, lies the equally remote Noshki-Chaghai region of Balochistan province.

Since 9/11 this region has been in turmoil. In the Baramcha area on the Afghan side of the border, the Taliban have a major base. From there they control militant activities as far afield as Nimroz and Farah provinces in the west, Oruzgan in the north and parts of Kandahar province in the east. They also link up with groups based in the Waziristan region of Pakistan.

Brazilian legend Ronaldo has confirmed his retirement from football.

The 34-year-old had a glittering career, helping Brazil win two World Cups and being named Fifa World Player of the Year in 1996, 1997 and 2002.

He had been expected to quit at the end of the season but the early elimination of his club, Corinthians, from the Copa Libertadores brought forward the date.

"I wanted to continue, but I can't. I think of an action, but I can't do it the way I want to. It's time," he said.

Ronaldo's career took him to some of Europe's top clubs, including Spanish rivals Barcelona and Real Madrid, as well as Italian neighbours AC Milan and Inter Milan.

But it was on the world stage where he made the biggest impact, scoring a record total of 15 goals at three World Cups.

Two security guards and an insurgent were killed in an attack in the Afghan capital Kabul, officials say.

Reports said the blast occurred just inside a shopping complex in the city centre after an attacker carrying explosives was challenged by guards.

A gun battle which broke out following the explosion has now ended.

It is the second attack in less than three weeks in the heavily fortified Afghan capital, after nine died in an attack on a supermarket on 28 January.

The Taliban told the BBC they had carried out that attack.

Monday's attack is thought to have begun when an attacker was challenged by security guards as he attempted to gain access to the shopping precinct, says the BBC's Quentin Sommerville in Kabul.

China has overtaken Japan as the world's second-biggest economy.

Japan's economy was worth $5.474 trillion (£3.414 trillion) at the end of 2010, figures from Tokyo have shown. China's economy was closer to $5.8 trillion in the same period.

Japan has been hit by a drop in exports and consumer demand, while China has enjoyed a manufacturing boom.

At its current rate of growth, analysts see China replacing the US as the world's top economy in about a decade.

Iranian police have fired tear gas at opposition demonstrators gathering in central Tehran in support of the protests in Egypt.

A BBC producer in the Iranian capital, who was affected by the gas, described central Tehran as "total chaos".

He said "severe clashes" were taking place between protesters and police and there had been many arrests.

Iranian police have placed opposition leader Mir Hossein Mousavi under house arrest, his official website says.

It says the move is intended to block him from attending the rally in Tehran.

The BBC's Mohsen Asgari in Tehran says thousands of people defied the government ban and gathered in the city centre chanting "death to dictators".