The Israeli embassy in London on Wednesday promised that the government would "ensure that justice is served" in the case of a British activist who died late Tuesday night, nine months after he was shot in the head by an Israel Defense Forces soldier in the Gaza Strip.

A statement from the embassy said that Jerusalem viewed the shooting with "the utmost severity" and was "acting to ensure that justice is served."

The IDF arrested a soldier late last year over the shooting of activist Tom Hurndall and charged him Monday with grievous bodily harm. Security sources said that with his death the charges were likely to be upgraded to manslaughter.

"After a full and independent investigation, charges have been brought against an IDF soldier in connection with the shooting of Mr. Hurndall, and a trial will take place," it said.

Hurndall, 22, died late Tuesday in the London hospital where he had been lying clinically dead after being shot in the head by a sniper on April 11 last year.

"Tom died last night just before 8 P.M.," his mother, Jocelyn Hurndall, said in a statement.

Hurndall's sister, Sophie, said Tom had contracted pneumonia. She said his death was a relief for the family, who had seen him lying in a coma for nine months.

"But obviously there is great sadness, because it's a time when we have to finally accept that we're not going to have Tom back," she told BBC radio.

The activist's supporters say he was wearing a bright orange jacket and helping Palestinian children cross a street under fire in the Gaza Strip town of Rafah when he was shot.

The soldier initially maintained he had opened fire on a man armed with a pistol, but later "admitted to firing in proximity to an unarmed civilian as a deterrent," according to the military.

British foreign office minister Baroness Symons said in a statement London would continue to urge the Israeli authorities "to pursue their investigations thoroughly."

She said recent progress on the case had been encouraging.

The soldier, who has not been named, has also been charged with obstruction of justice. The indictment followed months of lobbying by the family and the British Foreign Office for a thorough investigation.

"I'll be satisfied with nothing less than the most serious penalty for the soldier ... and for all those up the chain of command who were responsible for trying to stop the truth coming out," Jocelyn Hurndall said at the time. She had maintained that the accused soldier should face the more serious charge of attempted murder because he had been using a telescopic sight and had aimed to kill her son.

"We hope that prosecution of the soldier involved in the shooting of Tom will send a message to all soldiers in the occupied territories that they cannot commit breaches of human rights whether these be killing, maiming, humiliation, the destruction of homes or the collective punishment of whole communities," the Guardian quoted Jocelyn Hurndall as saying Wednesday.

"But I am extremely sceptical at the way the Israeli army has chosen to highlight certain facts about this particular soldier - that he had previously been arrested for smoking cannabis and is an Arab.

"This is a complete irrelevance and a deflection from the culture of impunity that is encouraged right along the chain of command right to the very top," she said.

The International Solidarity Movement (ISM), the pro-Palestinian peace group Hurndall was working with when he was shot, said on its Web site that a vigil would be held in central London on Wednesday to mark his death.