Palestinian officer shot dead

A Palestinian security services officer has been killed by Israeli troops, Palestinian sources say.

Sayad Abu Safra was said to be trying to stop a mentally retarded man approaching a Jewish settlement in the northern Gaza Strip when he was shot.

The Israeli army said a Palestinian man had been killed as troops tried to disperse a crowd of Palestinians.

The area is off limits to Palestinians to prevent militants from infiltrating the Nissanit settlement, it said.

The death came as senior Israeli and Palestinian officials were to hold informal talks to discuss various peace initiatives in London.

Israeli Prime Minister Ariel Sharon is facing pressure over the building Israel's controversial West Bank barrier.

Israel says it is needed to stop attacks by Palestinian militants.