The two Marines, 2nd Lt. Therrell S. Childers, 30, an infantry platoon commander with 1st Battalion, 5th Marine Regiment, and Lance Cpl. Jose Gutierrez, 22, a rifleman with 2nd Battalion, 1st Marine Regiment, died March 21 in separate clashes in southern Iraq. Both units are based at Camp Pendleton, Calif.

The sailor was identified as Lt. Thomas M. Adams, who was serving as an exchange officer with the Royal Navy’s 849 Squadron. Adams, 27, of La Mesa, Calif., was on one of the two Royal Navy Sea King helicopters that collided Saturday over the Persian Gulf. The squadron’s detachment is serving on the Royal Navy aircraft carrier HMS Ark Royal.

One of the Marine deaths occurred during a morning battle with Iraqi infantry forces at an oil pumping station while the other Marine died about 4 p.m. during at fight near the port of Umm Qasr, nearly 300 miles southwest of Baghdad.

Camp Pendleton officials did not immediately know which of the men was involved in which battle, nor the circumstances surrounding their deaths.

Childers and Gutierrez were both single. They joined the Corps in July 1990 and March 2002, respectively. In all, six Marines have been killed in the opening days of the war in Iraq.

On March 20, three Marines with the Camp Pendleton-based Marine Medium Helicopter Squadron 268 and a Marine from Marine Aviation Weapons and Tactics Squadron 1 at Marine Corps Air Station, Yuma, Ariz., died when their CH-46E Sea Knight helicopter crashed in Kuwait south of the Iraqi border.

Eight British Royal Marines on board as passengers also died in the crash.

David Castellon is the San Diego bureau chief for Navy and Marine Corps Times.