Tel Aviv - Israeli human rights groups have urged their government to investigate allegations of war crimes committed during the Gaza offensive, after a number of Israeli soldier told a symposium of lax rules of engagement that allowed civilians to be killed.

The nine groups, which include B'Tselem and the Association for Civil Rights in Israel, demanded the government's attorney-general establish an "independent" investigative body, not linked to the military, to examine the allegations.

The Israeli military announced Thursday that it had ordered an investigation into the allegations by the Criminal Investigation Division of the IDF (Israel Defence Forces) Military Police.

The Israeli Ha'aretz daily Thursday published some of the soldier's testimonies to the symposium held last month at a college in northern Israel.

One soldier described how a sniper shot dead a mother and her two children from the roof of a house, after soldiers on the ground floor had failed to inform him he should hold his fire because they were ordering the families living in the building to leave.

"The platoon commander let the family go and told them to go to the right. One mother and her two children didn't understand and went to the left, but they forgot to tell the sharpshooter on the roof they had let them go and it was okay, and he should hold his fire," said the soldier.

"I don't think he felt too bad about it, because after all, as far as he was concerned, he did his job according to the orders he was given. And the atmosphere in general, from what I understood from most of my men who I talked to ... I don't know how to describe it .... The lives of Palestinians, let's say, is something very, very less important than the lives of our soldiers," said the squad leader.

Another squad leader from the same brigade told of an incident where the company commander ordered that an elderly Palestinian woman be shot and killed. She was walking on a road about 100 meters from a house the company had commandeered.

He said he argued with his commander about the permissive rules of engagement, but after the orders were changed, his soldiers complained that "we should kill everyone there [in the center of Gaza]. Everyone there is a terrorist."

He said some soldiers also wrote "death to the Arabs" on the walls of a house and spat on family pictures.

The Israeli rights groups said they sent a letter to Israeli Attorney General Menahem Mazuz, noting the government's failure to establish an independent investigation constitutes a violation of Israel's responsibilities under international law.

The Israeli military had a history "of failures to investigate suspicions of serious crimes and illegitimate officer orders," they charged in a statement sent to the media.

More than 1,400 Palestinians were killed and some 5,000 injured during the 22-day offensive, launched December 27 in a bid to curb rocket and mortar attacks from the strip at southern Israel.

According to the Gaza-based Palestinian Center for Human Rights (PCHR), two-third of them were civilians. It has published a list with the names of all fatalities.

Thirteen Israelis were also killed during ground fighting, some by friendly fire, or by Palestinian rockets. (dpa)