U.S. troops killed and wounded in Helmand were accompanying Afghan forces

Washington: The one U.S. trooper killed and two wounded in Afghanistan`s southern Helmand province were accompanying Afghan special operations forces when they came under fire, Pentagon spokesman Peter Cook said on Tuesday.

There may still be U.S. troops in the area engaging with enemy forces, Cook said, adding that some Afghan forces were also wounded in the attack.

"My understanding is that there may still be Americans on the ground in this immediate situation engaging with the enemy in support of Afghan forces," Cook said. "This is a fluid situation."

Two U.S. medical evacuation helicopters were sent to provide assistance, Cook said. One was waved off after taking fire and returned to its base. The second landed but struck a wall and damaged its rotor blades, and remains on the ground, Cook said.