Updated

The Taliban took responsibility Monday for a bomb blast in Afghanistan that killed six American troops, while other militants launched suicide attacks on two police headquarters that according to officials left seven attackers and two children dead.

German Brig. Gen. Gunter Katz, a spokesman for the U.S.-led coalition, said the six Americans were killed on Sunday when their armored vehicle struck a bomb planted in eastern Afghanistan. He said a seventh American soldier was killed in a separate insurgent attack in the south.

Taliban spokesman Zabiullah Mujahid claimed responsibility for the attack in Wardak province, just south of Kabul, in a statement. They were the latest American casualties from bombs planted by insurgents along roads, paths or mountain tracks.

Coalition and Afghan forces are trying to secure areas of Wardak that insurgents use as gateway into the Afghan capital where they stage high-profile attacks on Afghan government and NATO targets.

Wardak provincial police chief Gen. Abdul Qayum Baqizoi said that after the explosion in Jalrez district, a coalition airstrike killed a local Taliban commander and wounded three insurgents.

In the south, three suicide bombers riding in a three-wheeled vehicle blew themselves up Monday afternoon in Kandahar city, killing two children and wounding six other civilians, said Kandahar provincial spokesman Ahmad Jawed Faisal.

A short time later, three more suicide bombers tried to attack the police headquarters in Kandahar, but were gunned down by police before they could get into the compound, Faisal said. The incident was still being investigated, but Faisal said authorities suspect that the three attackers in the vehicle, a form of miniature pickup known as a zaranj, were headed toward police headquarters when their explosives detonated prematurely.

Two policemen and four civilians were wounded in the 90-minute gun battle around the police headquarters.

A surge in Afghan and coalition forces during the past two years has routed Taliban fighters from many of their strongholds in the south, but the insurgents have stepped up their attacks this summer to take back key areas.

Militants also attacked a police headquarters building in Shibirghan, the capital of Jawzjan province in the north.

Provincial governor Mohammad Aleem Saaie said a suicide attacker on a bicycle blew himself up near the headquarters. He said 26 people were wounded, including two policemen, a doctor and a prosecutor.

"This was another attack against innocent civilians," said Gen. Abdul Aziz Ghairat, the provincial police chief. "The majority of the wounded people are civilians."

In other violence, authorities said gunmen assassinated a chief prosecutor in Ghazni province in eastern Afghanistan Monday morning as he drove to work. Mohammad Ali Ahmadi, the deputy provincial governor, said Sahar Gul was shot twice -- once in the head and once in the chest.

The Taliban routinely target Afghan government officials to weaken support for President Hamid Karzai's administration.

Separately, President Hamid Karzai on Monday condemned the public killing of a married Afghan woman who was accused of allegedly running off with another man.

In a statement, Karzai called the execution-style slaying an unforgiveable crime. A video of the killing, which surfaced recently, showed the woman being shot multiple times as people stood nearby cheering.

Before it collapsed in 2001, the hardline Taliban regime carried out public executions of women, mostly for adultery.

Police in Shinwari district of Parwan province say the Taliban were behind the woman's slaying, which occurred about up to 12 days ago.

Karzai's condemnation comes as donor nations met in Tokyo to pledge $16 billion in aid for Afghanistan. The donors expressed strong concerns over how the money will be handled and also called on Kabul to improve human rights, especially women's rights.

"Such a crime is unforgivable in the sacred religion of Islam and the laws of the country," Karzai said.

The U.S. Embassy in Kabul and the top commander of U.S. and NATO forces on Sunday also condemned the killing of the woman.