The U.S. military says two Marines were killed when their helicopter crashed outside the western Iraqi town of Ramadi Wednesday.

A military spokesman said the cause was under investigation. He gave no further details of the incident.

Meanwhile, U.S. officials say they are stepping up counterinsurgency training for officers arriving in Iraq, following one of the deadliest months for U.S. troops in the country.

General Peter Pace (l) with Donald Rumsfeld at the Pentagon

The New York Times says Marine and Army officers will be trained at a new school in Taji, north of Baghdad, on the latest tactics for finding and destroying roadside bombs and dealing with Iraq's many insurgent factions.

Tuesday, the top U.S. general, Chairman of the U.S. Joint Chiefs of Staff General Peter Pace said he was not surprised at the high number (93) of U.S. casualties in Iraq last month, noting that increased attacks were linked to Iraq's October 15 constitutional referendum.

Iraqis are to elect a new government next month.

 Some information for this report provided by AFP and AP.