Camp Pendleton, California: The US Marine sergeant accused of leading a 2005 massacre of Iraqi civilians in Haditha gunned down five unarmed men who were standing next to a car after a roadside bombing, a Marine from his squad has told a military court.

Sgt Sanick Dela Cruz also testified that, about a week before the incident at Haditha, another bombing prompted Staff Sgt Frank Wuterich to say the squad should "kill everybody in the vicinity" if they were hit again.

Dela Cruz took the witness stand against his former squad leader at a hearing to determine if Wuterich, 27, should face court-martial over the November 19, 2005, events at Haditha.

Iraqi witnesses say US troops massacred two dozen unarmed men, women and children at Haditha in retaliation for the death of Lance Cpl Miguel "T.J." Terrazas in the roadside bomb.

Bomb

Defence lawyers say the civilians died during a chaotic house-to-house battle in the western Iraqi town. The hearing into Wuterich's conduct was expected to last several more days. Dela Cruz, granted immunity from prosecution in the case after murder charges against him were dismissed in April, told the court that after the bomb exploded under a Humvee in their four-vehicle convoy he saw the five Iraqi men standing near a white car across the street.

In a matter of seconds one of the men dropped dead on the ground, Dela Cruz said, and he looked around to see Wuterich kneeling and firing on the group. By the time he reached the white car, Dela Cruz said, all of the Iraqis had been killed. "They were in a pile, sir, laying dead, sir," said Dela Cruz.