A Palestinian boy attends a protest in reaction to the death of Mustafa Tamimi, in the West Bank city of Ramallah, December 10, 2011. Tamimi, a Palestinian demonstrator injured by Israeli soldiers in the occupied West Bank, died of his wounds on Saturday, a hospital spokeswoman and protest organisers said. (MOHAMAD TOROKMAN/REUTERS)

A Palestinian protester who was struck in the face by a tear-gas canister fired at close range by an Israeli soldier during a clash in the West Bank died of his injuries Saturday, prompting an army investigation into what human rights advocates said was a violation of military regulations.

Mustafa Tamimi, 28, was hurling rocks at an armored military Jeep in the village of Nabi Saleh on Friday when a rear door of the vehicle opened and a soldier fired a tear-gas canister at him from a few yards away, according to witnesses and photos taken at the scene. He was taken to an Israeli hospital, where he died the next day.

The army said it was investigating the incident, in which it said troops dispersed “a violent and illegal riot.”

Residents of Nabi Saleh stage weekly demonstrations to protest the seizure of village land by a neighboring Israeli settlement. The marches are routinely broken up with tear gas and often develop into stone-throwing confrontations between local youths and Israeli troops.

Sarit Michaeli, a spokeswoman for the Israeli human rights group B’tselem, who was in Nabi Saleh, said she had documented scores of cases in which Israeli soldiers and border policemen fired tear-gas canisters directly at protesters, in violation of explicit regulations.

Michaeli said that while B’tselem has received letters from top military and legal officials stating that it was prohibited to aim tear-gas canisters directly at protesters, the practice was in fact common. “Tear gas is a means to disperse demonstrations,” she said. “It is never allowed to use a tear-gas canister as a weapon.”

In two similar incidents during protests in West Bank villages in 2009, a Palestinian was killed when he was hit in the chest with a tear-gas canister and an American activist suffered serious brain damage when a canister struck him in the head.