LONDON (Reuters) - An Israeli tank crew who killed a Reuters cameraman and eight young bystanders in the Gaza Strip four months ago acted properly and will not face legal action, Israel's senior military lawyer has concluded.

The military advocate-general told the international news agency in a letter sent on Tuesday that troops could not see whether Fadel Shana was operating a camera or a weapon but were nonetheless justified in firing a shell packed with darts that killed him and eight other Palestinians aged between 12 and 20.

Reuters said on Wednesday it was deeply disturbed by a conclusion that severely curtails the freedom of the media to cover the conflict by effectively giving soldiers a free hand to kill without being sure they were not firing on journalists.

Shana, 24, filmed two tanks positioned about 1.5 km from where he was standing for several minutes before, in a chilling final 2 seconds of video, his camera captured one tank firing a shell that burst overhead, showering the journalist and others with thousands of metal darts known as flechettes.

"The tank crew was unable to determine the nature of the object mounted on the tripod and positively identify it as an anti-tank missile, a mortar or a television camera," Brigadier General Avihai Mendelblit of the Israel Defence Forces wrote.

But the military lawyer cited an attack that killed three IDF soldiers in another part of the enclave earlier in the day, a separate grenade attack on a tank, the fact that Shana and his soundman who was wounded were wearing body armour -- "common to Palestinian terrorists" -- among reasons for suspicion.

Their blue flak jackets, like the car, were marked "PRESS". The army said the troops could not see those signs. Journalists in Gaza say they have rarely seen militants wear flak jackets.

Mendelblit wrote: "In light of the reasonable conclusion reached by the tank crew and its superiors that the characters were hostile and were carrying an object most likely to be a weapon, the decision to fire at the targets ... was sound ...

"There is no doubt that Fadel Shana's death is a tragedy...

"A journalist in action was killed by IDF fire, along with others not involved in the hostilities.

"However ... the available evidence does not suggest misconduct or criminal misbehaviour ... I have therefore decided ... that no further legal measures will be taken."

Reuters Editor-in-Chief David Schlesinger said: "I'm extremely disappointed that this report condones a disproportionate use of deadly force in a situation the army itself admitted had not been analysed clearly.

"They would appear to take the view that any raising of a camera into position could garner a deadly response."

Reuters wrote to Mendelblit on Wednesday with a number of questions, including asking precisely why the soldiers ruled out the possibility that Shana was a cameraman, why the fact he stood in full view of the tanks for some minutes did not suggest he had no hostile intent and why the tank crew, if concerned but unsure, did not simply reverse a few metres out of sight.

In Jerusalem, the Foreign Press Association said it was disappointed with a report that seemed to give soldiers licence to fire on journalists without being sure of their target.

In New York, Joel Campagna of the Committee to Protect Journalists said: "These findings mean that a journalist with a camera is at risk of coming under fire and there's not that much that can be done. That's unacceptable.

"It's difficult to believe ... that the IDF took the necessary precautions to avoid causing harm to civilians -- as it is obliged to do under international law."