Kabul ? A U.S. Air Force F-15E Strike Eagle fighter jet crashed early Saturday in central Afghanistan, killing the two crew members, the U.S. military said.

Also Saturday, a suicide driver blew up his explosive-laden vehicle next to an Afghan army convoy in Zabul province, killing three soldiers and wounding three others, Defense Ministry spokesman Mohammad Zahir Azimi said.

A statement by the Air Force Central Command said the crash was not due to hostile fire, and a board of officers would be convened to determine the cause. Names of the crew members were not released. Their deaths bring to 50 the number of international service members killed in Afghanistan in July — already the deadliest month of the war for NATO forces.