A US Apache helicopter crashed during a routine training mission in Afghanistan, injuring the two crewmen aboard, a military statement said.
The AH-64 Apache came down last night near Bagram, the main base for US-led forces in Afghanistan to the north of the capital, it said.
The military also said two US servicemen and their Afghan interpretor were hurt today when their patrol was hit by a makeshift bomb in the central province of Uruzgan.
US-led forces have lost at least a dozen helicopters in Afghanistan due to technical problems, operating conditions or hostile fire since invading the country to overthrow the radical Taliban government in late 2001.
The statement said yesterday's crash was not believed to have been caused by insurgents, but it comes a day after a giant Chinook CH-47 helicopter was destroyed by a hard landing during an operation to hunt down insurgents in the restive south.
Taliban guerrillas said they had shot down the chopper in Thursday's incident, but had no proof. There were no casualties.