KABUL, Afghanistan (AP) - A military helicopter crashed during

an early morning operation in southern Afghanistan on Monday,

killing three Australian commandoes and an American service member,

officials said.

The crash was being investigated but there were no indications

of enemy involvement, NATO said in a statement.

The Australian government said three of the dead were

Australians, and U.S. Lt. Col. Joseph T. Breasseale said the fourth

service member killed was American.

Australian Air Chief Marshal Angus Houston said seven other

Australian soldiers were wounded, two of them badly.

The crash comes in a particularly deadly month for NATO forces.

Included the most recent deaths, at least 57 international troops,

including 35 Americans, have died so far in June. That could make

June among the deadliest for international forces in the nearly

nine-year war. The deadliest month so far for the military alliance

was July 2009 when 75 troops, including 44 Americans, were killed.

The helicopter crashed before dawn in southern Kandahar

province, and the operation it had been part of was still ongoing,

Houston said.

Other coalition helicopters that were part of the same push

landed near the downed aircraft and airlifted out the wounded, he

said. More details on the operation were not given.

NATO has launched a major operation to secure the biggest

southern city, Kandahar, the provincial capital that was the

Taliban's spiritual birthplace.

There were 15 people aboard the helicopter, 10 of them

Australians, said Australian Defense Minister John Faulkner.

Australia has some 1,500 troops in Afghanistan alongside NATO

forces. Monday's deaths take Australia's military death toll in

Afghanistan to 16.

Australia's 1,550 troops in Afghanistan are based mainly in

Uruzgan province, and are mostly involved in training Afghan

security forces.