A suicide bomber on a bicycle has struck outside the Afghan Defence Ministry, killing at least nine civilians as US Defence Secretary Chuck Hagel visited Kabul, officials said.
The Taliban claimed responsibility for the attack in the Afghan capital, and said it was meant as a message to the US defence chief.
Pentagon spokesman George Little said Mr Hagel was in a briefing at a US-led military coalition facility in another part of the city when the explosion occurred. He said the briefing continued without interruption.
Afghan Defence Ministry spokesman General Mohammad Zahir Azimi said the bomber on a bicycle struck just before 9am local time about 30 yards from the main gate of the ministry.
A man at the scene, Abdul Ghafoor, said the blast rocked the entire area.
"I saw death bodies and wounded victims lying everywhere," Mr Ghafoor told AP Television News. "Then random shooting started and we escaped from the area."
The ministry said at least nine civilians were killed and others were wounded.
Reporters travelling with Mr Hagel were in a briefing when they heard the explosion.
They were moved to a lower floor of the same building as US facilities in downtown Kabul were locked down as a security precaution.