JERUSALEM: An Israeli army murder inquiry into a soldier's killing of a supine and wounded Palestinian assailant, the first such legal proceedings in six months of street violence, triggered friction on Sunday within Prime Minister Benjamin Netanyahu's cabinet.

Video taken by Israel's B'Tselem human rights group showed the infantryman firing on Thursday into the head of a Palestinian as he lay on the ground, still moving, in Hebron in the occupied West Bank. Minutes earlier, the Palestinian had stabbed and wounded another soldier.

The soldier has been arrested on suspicion of murder, the military said, and could become the first member of the Israeli armed forces to be charged with murder since a wave of Palestinian attacks, often met with lethal response, erupted in October.

Education Minister Naftali Bennett, who heads the far-right Jewish Home party in the coalition government, cautioned against murder charges. Israeli media said Bennett sparred with Netanyahu over the issue at Sunday's cabinet meeting.

The Hebron incident brought to the boil a debate in Israel over whether excessive force has been used against Palestinian assailants. Palestinian leaders have accused the Israelis of routine extra-judicial killings - a charge that Israel denies.

According to Army Radio, the soldier arrived on the scene after other troops determined the Palestinian no longer posed any danger, and twice told comrades he "deserves to die".

The infantryman's family said he had feared the Palestinian might set off a hidden bomb. Supporters circulated an online petition demanding that he be decorated for bravery.

"I state here that this soldier is not a murderer, and that prosecution on a murder clause would be a total loss of control," Bennett told Israel Radio in remarks echoed by other ministers, including from Netanyahu's rightist Likud.

"Someone got confused between the bad guys and good guys .. and I intend to ensure that the soldier has a just trial and not a show trial," Bennett said.

Benjamin Netanyahu, responded to the shooting with measured censure, saying the soldier's action "does not represent the values of the IDF (Israel Defence Forces)".

He sounded even more circumspect on Sunday.

"IDF troops, our children, adhere to high moral standards as they bravely fight blood-thirsty murderers in tough operational circumstances," he told his cabinet in broadcast remarks. "I am certain that in any event, including the current incident, the inquiry takes all of the conditions into account."

The past six months has seen the worst period of sustained violence in the West Bank, Jerusalem and the Israeli interior since the second Palestinian uprising ended a decade ago.

Palestinians have killed 28 Israelis and two US citizens in knife, car-ramming or gun assaults. At least 190 Palestinians, 129 of whom it says were assailants, have been killed by Israeli forces. Many others were shot during clashes and protests.

Israel has stepped up training meant to keep troops' shooting accurate and restrained - including at nine hi-tech ranges where they respond with laser-firing rifles to simulated Palestinian attacks on an interactive screen.

"The first time the soldiers try it out, 30 percent fail - either by freezing up, or through improper shooting of bystanders or of terrorists who no longer pose a threat," Nadav Sheetrit, who runs the Bagira Systems Ltd simulator at Camp Tsur infantry training base, told a visiting Reuters reporter.

By the second try, the pass rate is 99 percent, he said.