Mustafa Tamimi died on Saturday, a day after he was struck in the face by a tear-gas canister fired at close range from an armoured military jeep in Nabi Saleh, a village in the West Bank that has seen weekly protests against the Israeli occupation.

Israeli military officials have been largely unapologetic for the death, releasing pictures of a sling they said was found on Mr Tamimi's body as evidence that the dead man had thrown stones.

A number of military officials took to Twitter to defend the army and attack Mr Tamimi, but none caused as much outrage as a post by Maj Peter Lerner, spokesman for the Israel Defence Forces (IDF) Central Command, who appeared to suggest that the Palestinian deserved his fate.

"What was Mustafa thinking running after a moving jeep while throwing stones #fail," he wrote as the Palestinian fought for his life in hospital.

"Fail", and its stronger variant "epic fail", are American slang terms, popular on the internet, used in a derogatory fashion to denote extreme stupidity.

Activists said that Maj Lerner's choice of language was symptomatic of a culture of indifference to Palestinian rights within the Israeli army.

"I think it is important to remember that this is the official spokesman of the IDF Central Command and it shows what the army thinks of a Palestinian life," said Jonathan Pollack, an Israeli pro-Palestinian activist.

"Mustafa was killed in cold blood, shot from inside an army vehicle at close range."

Pictures of Mr Tamimi lying in a pool of blood, his face badly mangled, have raised tensions in the West Bank. Clashes erupted at his funeral yesterday as Israeli soldiers fired tear gas at mourners attempting to march on a spring near Nabi Saleh which has been taken over by Jewish settlers.

At least five people were injured, including Mr Pollack who was admitted to hospital after he was held in a chokehold by Israeli soldiers, causing him to lose consciousness.

Maj Lerner denied mocking Mr Tamimi, saying his use of the word "fail" was directed at activists who, he said, had given a one-sided version of the incident.

"I did not mean to hurt anyone's feelings by writing 'fail'," he said. "I felt the need to point out that none of the pictures of Tamimi prior to the incident were published despite the fact that he was throwing stones."

The IDF has launched an investigation into the incident. Under army rules, soldiers are forbidden from firing tear gas canisters directly at protesters. A spokesman insisted that the army normally responded to demonstrations with "extreme restraint".

The eruption of weekly protests in the West Bank over the past two years has unnerved the Israeli military establishment.

A leaked US diplomatic cable, written last year, quoted a senior Israeli officer as saying that "even demonstrations that appear peaceful" would not be tolerated and would be broken up.

Conceding that non-violent protests presented a particular challenge to Israeli control of the West Bank, the cable quoted Gen Amos Gilad, a senior defence ministry official, as saying: "We don't do Gandhi very well."

The Israeli army's actions in Nabi Saleh have been criticised in the past after a number of children were detained and allegedly subjected to sleep deprivation and threats during interrogation to force them to incriminate adults who participated in the demonstrations.