By Ryan Browne, CNN

(CNN) -- Three US service members were killed by an improvised explosive device near Bagram Air Base in Afghanistan on Monday, according to the US military. Three other US service members and a contractor were wounded.

A statement from the military said the wounded service members have been evacuated and are receiving medical care. The Taliban claimed credit for the attack, which involved a car bomb targeting a US military convoy near one of America's largest military facilities in Afghanistan.

On Tuesday the Secretary of the Navy, Richard Spencer, told the Senate Armed Services Committee that the three killed US service members were US Marines.

"We feel and mourn the loss of these Americans with their families and loved ones. They volunteered to protect their country. We will continue our mission," Gen. Scott Miller, the commander of US and NATO forces in Afghanistan, said in a statement on Tuesday.

The US military initially said that a contractor was also killed in the attack however on Tuesday it issued a statement saying that the contractor, an Afghan citizen, was wounded in the incident and treated on the scene along with injured Afghan civilians.

Seven US service members have been killed in Afghanistan this year.

The US has about 14,000 troops in Afghanistan, where they primarily advise Afghan forces battling the Taliban and the local ISIS affiliate.

While US officials have said that peace talks with the Taliban have made progress, they have yet to finalize any agreements and intense fighting between the government and the insurgency continues.

The US envoy to the peace talks, Ambassador Zalmay Khalilzad, left Afghanistan on Sunday following meetings with Afghan president Ashraf Ghani.

This article has been updated with a Tuesday statement from the US military and comments from the commander of US forces in Afghanistan.