A suicide bomber blew himself up at a bank close to the heavily protected US embassy compound in the Afghan capital today, killing at least four people and wounding several, the interior ministry said.

The bomber hit the entrance to a Kabul Bank branch in the well-off area of Kabul, close to the main diplomatic quarter, ministry spokesman Najib Danish said.

It was not immediately clear how many casualties had been caused by the explosion, which came as banks were busy with people withdrawing money ahead of the Muslim Eid holiday at the end of the week.

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Danish said at least four people had been killed and three wounded while the public health ministry said separately that one dead and eight wounded had been brought to city hospitals.

There was no immediate claim of responsibility. A spokesman for the Taliban, who are seeking to reimpose Islamic law after their 2001 ouster by U.S.-led troops, said he was checking reports.

The latest in a long series of suicide attacks in Kabul highlight the danger in the Afghan capital, where 209 civilians were killed and 777 injured in the first half of the year alone, according to United Nations figures.

President Ashraf Ghani's government has started tightening security around the centre of the city, where many of the most deadly attacks have taken place.