A blast which rocked the Afghan capital on Saturday was accidental, NATO said, as Washington's military chief arrived to explain the sacking of the US commander of foreign forces in the country.
The blast, near the foreign ministry in Kabul's embassy district, happened when an anti-personnel mine in an Afghan army vehicle accidentally detonated, a spokesman for NATO's International Security Assistance Force said.
It was not an attack by Taliban-linked insurgents, Lieutenant-Commander Ian Baxter told AFP of the blast, which happened around 9:55 am (0525 GMT).
The blast shook Kabul after US Admiral Mike Mullen, chairman of the US Joint Chiefs of Staff, arrived late Friday on a mission to reassure Afghan leaders following the sacking of the top commander.
Police on the scene told AFP there were no casualties.
General Mohammad Zahir Azimi, spokesman for the defence minister, said the Afghan National Army driver of the truck had been detained for questioning.
Mullen was set to meet Afghan President Hamid Karzai, the presidential office confirmed, after US General Stanley McChrystal was sacked for insubordination.
During his one-day visit, Mullen was also due to meet US and NATO officials, the US embassy said.
Mullen was expected to explain the circumstances leading up to McChrystal's sacking and reassure Karzai that a change of leadership did not mean a change of tactics.
"My message will be clear. Nothing changes about our strategy. Nothing changes about the mission," said Mullen at a press conference in Washington before his departure for Afghanistan and Pakistan.
General David Petraeus has been appointed as the new commander, a move that Defense Secretary Robert Gates said was the "best possible outcome to an awful situation".
Speaking at the same press conference Thursday as Mullen, Gates said there was progress in the Afghan war -- the administration's latest bid to defend the mission as foreign troop casualties hit record highs in the nearly nine-year war.
NATO announced the death of another alliance soldier following a Taliban-style bomb attack in southern Afghanistan on Saturday.
June has become the deadliest month of the war since it began in late 2001, with 85 foreign troop deaths, according to an AFP tally based on that kept by icasualties.org.
This year 305 foreign soldiers have been killed -- compared with a 2009 total of 520 -- under McChrystal's strategy to pour tens of thousands of extra troops into Afghanistan to take the fight to the Taliban.
McChrystal won early praise for a drop in civilian casualties as he attempted to win popular trust, at the same time working hard to bring Karzai on board.
His dismissal after comments he made in a magazine was met with dismay in Kabul, where Afghans and foreign diplomats praised his efforts to change the course of the war.
There are 140,000 troops in Afghanistan, with the number set to peak at 150,000 by August in the hope of forcing an end to the insurgency by ramping up efforts in the southern province of Kandahar, the Taliban's heartland.
Obama said in Washington that Petraeus, well regarded for his role in turning around the Iraq war, would be able to hit the ground running due to his work on Afghanistan as head of Central Command, which oversees both war zones.
British Prime Minister David Cameron said on Friday that he wanted troops home from Afghanistan before the next British general elections, due by 2015.
"We can't be there for another five years, having been there for nine years already," Cameron, who took office last month, told Sky News television, on the sidelines of a Group of Eight summit.