A Palestinian on his way to a carry out a car bombing killed an Israeli policeman when he detonated his explosives prematurely on Monday, in what Israel said was the fifth attempted suicide attack in 24 hours. Israeli police said the Palestinian bomber was also killed in the explosion as police officers approached his car near the Jewish settlement of Maale Adumim on a towering West Bank hill just outside Jerusalem. A surge of tit-for-tat violence in the past week has increased pressure on Prime Minister Ariel Sharon from the political right, which wants tougher action to end Palestinian attacks, and the left wing which wants peace talks.