An American service member was fatally wounded by insurgent fire in southern Afghanistan, the U.S. military said Sunday, bringing to at least 39 the number of U.S. troops killed this month in the country.

Officials released no other details about the Saturday battle, which was reported by the NATO command. A U.S. military spokesman, Navy reservist Lt. j.g. Tommy Groves, would only confirm that the service member was American.

July has been the deadliest month for U.S. and NATO forces in the Afghan war. Some 60,000 U.S. forces now operate in Afghanistan — a record number. President Barack Obama has increased the U.S. focus on Afghanistan as American troops pull out of Iraq.

Overall, at least 68 international troops have died in July.

Also Sunday, one of President Hamid Karzai's vice presidential running mates in next month's election escaped injury when his convoy came under fire in northern Afghanistan, officials said.

Mohammad Qasim Fahim, the former commander of the Northern Alliance that helped oust the Taliban in 2001, was traveling from Kunduz to Takhar province when militants opened fire on his 30-vehicle convoy, according to Kunduz Gov. Mohammad Omar.

A Karzai aide, Abdul Jalal, said one cameraman working for the campaign was wounded and Fahim's armored car was struck by bullets but the candidate was not hurt.