Palestinian officials said on Sunday they had arrested a member of their peace negotiating department for spying for Israel, a development likely to deepen distrust between the sides at a time of deadlocked diplomacy and heightened violence.

The man, whose name was not released, is part of the management staff in the umbrella Palestine Liberation Organization’s (PLO) negotiations department and is accused of “collaborating with Israel”, a security official told Reuters.

Another official said the suspect was arrested two weeks ago.

Al Ayyam newspaper, published in the West Bank city of Ramallah where Palestinian President Mahmoud Abbas’s U.S.-backed administration is based, described the suspect as a 20-year veteran of the PLO team and said he had confessed to the charge.

How long he had spied for Israel and what damage he might have done remained unclear, Al Ayyam said, citing an unnamed senior Palestinian official.

Israeli officials did not immediately respond.

The PLO and Israel signed interim accords in 1993 that won limited self-rule for the Palestinians, but after several rounds of talks their goal of statehood in the occupied West Bank, East Jerusalem and in the Gaza Strip remains out of reach.

The stalemate, as well as Muslim anger over perceived Jewish encroachment on a contested Jerusalem shrine, has contributed to Palestinian street attacks and protests that erupted in October and have drawn a tough response from Israeli security forces.

In the latest incident, a female resident of the settlement of Otniel in the southern West Bank was stabbed to death in her home when an assailant broke into her house and attacked her, the Israeli army and a local settlement official said.

The military added that troops were searching for the assailant, who had fled the scene, and a neighbor in the settlement told Army Radio that residents had been told to lock themselves inside their homes and keep away from windows.

Earlier in the day, a Palestinian was shot dead when he tried to stab Israeli soldiers near the West Bank town of Nablus, the army said.

Since Oct. 1 when the upsurge in violence began, Palestinian stabbings, car-rammings and gun attacks have killed 25 Israelis and a U.S. citizen.

In the same period, at least 148 Palestinians have been killed, 94 of whom Israel has described as assailants. Most of the others died during violent demonstrations.

REUTERS