A Taliban suicide bomber wounded three civilians when he blew himself up as he was challenged by police in the Afghan capital, Kabul, on Tuesday, the Interior Ministry said.

Taliban militants have launched some 100 suicide attacks so far this year, mostly targeting Afghan and international security forces, but as much as 80 percent of their victims are civilians, security experts say.

The bomber struck early in the morning in the Gozargah area of the capital, next to the walls of the historic tomb of Babur, the 16th century founder of India's Mughal dynasty. Only a leg of the bomber remained, lying on the ground.

"It was an attack next to be Babur gardens," said Interior Ministry spokesman Zemarai Bashari. "The suicide bomber wanted to get into the (centre of the) city, but there was a strong security checkpoint of the police so he was not able to infiltrate.

"He jumped out of the car and detonated himself, as a result of that, fortunately, we do not have a big number of casualties. Only three people are injured, civilians," he said.

Police challenged the bomber as he approached a checkpoint, another ministry official said.

Earlier, a police official had said three people had been killed.

The Taliban claimed responsibility for the attack and said it targeted an Afghan army bus, but there were no buses in the area at the time.

Bomb attacks in Kabul are comparatively rare compared with cities in the south and east, where the Taliban insurgency is concentrated.

The Taliban have carried out about the same number of suicide attacks in Afghanistan so far this year compared with the same period last year. But security forces have prevented a much greater number of potential attacks, indicating a degree of success on their part, but also that the militants are attempting far more suicide bombings, security experts say.

Afghan forces beefed up security in Kabul early this year in an attempt to clamp down on suicide bombings, but still some militants have got through the cordon.

A suicide car bomber killed 58 people and wounded well over 100 in an attack on the Indian Embassy in Kabul on July 7, the most deadly incident in the capital to date.