A suicide bomber blew himself up near a U.N. office in Afghanistan's eastern Khost province Sunday, injuring himself and a woman, provincial police chief Mohammad Ayub said.

"The man with explosive device tied to his body detonated himself in front of a U.N. office in Khost city, the capital of Khost province at around 8:20 a.m. local time, wounding a woman," Ayub told Xinhua.

He said that one hand of the bomber was cut off in the explosion and he was sent to hospital.

Eyewitnesses said the man was planting a mine on the road which suddenly exploded, also injuring a passer-by woman.

It is unknown what was exactly the target in the blast and no one has claimed responsibility for it.

Anti-government militants, who are fighting Afghan government and foreign troops based in Afghanistan, in the past have targeted international institutions.

Spiraling insurgency-related violence and conflicts left 8,000 people dead across Afghanistan last year during which over 140 suicide blasts were recorded.

(Xinhua News Agency June 8, 2008)