2 U.S. Marines killed in Afghanistan

KABUL, Afghanistan (CNN) - Two U.S. Marines died Saturday as a result of improvised explosive device strikes in Afghanistan, the International Security Assistance Force said Sunday.

The ISAF corrected an earlier report that four U.S. Marines had been killed.

A third U.S. service member died Friday at home from wounds sustained in Afghanistan in June, the military said.

The deaths bring to 647 the number of U.S. troops killed in Afghanistan since military action there began in October 2001.

The ISAF did not release the casualties' nationalities, but U.S. Forces in Afghanistan had confirmed earlier the service members were from the United States.

–CNN's Atia Abawi contributed to this report.