Israeli advances leave four dead

Israeli troops have entered two West Bank towns killing four palestinians in gun battles as they advanced.

The tanks entered the towns of Qalqilya and Tulkarem in the northern West Bank were they were met by Palestinian gun fire.

In Qalqiliya, Israeli soldiers took over the police headquarters, which Palestinian officers had left before the incursion.

Troops also seized the rooftops of four homes and set positions there.

A Palestinian policeman and an activist in the Islamic militant group Hamas was killed, doctors say.

Israeli soldiers arrested five Hamas activists, including four brothers of a man who had carried out a suicide bombing in Israel in 1994.

Two members of Force 17 were also detained.

In nearby Tulkarem, Israeli tanks shelled a Palestinian police outpost, killing two policemen.

The Israeli army confirmed the incursions, and said they were launched to protect Israeli citizens.