KABUL, Aug 21: Four US soldiers were killed and three wounded in a bomb attack in Afghanistan on Sunday as they were trying to clear militants from an area before an election next month, the US military said.

Hours later, two US embassy staffers were hurt when their vehicle was hit by a blast near the capital, Kabul.

US forces have now suffered 47 deaths in combat in Afghanistan this year, making it the worst period since they arrived to oust the Taliban in October 2001.

The wounded soldiers were hurt in secondary explosions as they tried to pull fellow soldiers to safety after the first blast in Zabul province, in the south of the country.

“Attacks such as this strengthen, not weaken, the resolve of the US/Coalition, Afghan National Security Forces and the Afghan people,” said a US commander, Maj-Gen Jason Kamiya.

The Taliban claimed responsibility for the attack in Dai Chopan district. A Taliban spokesman, Abdul Latif Hakimi, speaking by telephone from an undisclosed location, said Taliban fighters had planted the bomb.

Two Afghan government soldiers were killed in a similar blast in another part of troubled Zabul, a provincial official said.

The US unit was involved in operations in support of the Sept 18 parliamentary and provincial elections, which the Taliban and other militants have condemned and vowed to disrupt.

“The unit’s mission is part of a much larger operation to disrupt enemy forces and, thereby, provide a safe environment for upcoming elections,” the US military said.

ROUTINE MISSION: In Kabul, a US embassy spokesman confirmed that two staffers had been hurt in a blast, but declined to identify them.