A suicide car bomber killed 10 people, including four children, Saturday at a police checkpoint on the outskirts of the northwestern Pakistani city of Peshawar, in the latest in a string of militant attacks targeting the city, officials said. Peshawar has been a main focus of the attacks, which in the last week alone have killed over 50 people, including 10 at the regional offices of Pakistan's top intelligence agency, which was targeted by a massive truck bombing Friday. The agency, Inter Services Intelligence, has been overseeing much of the country's anti-terror campaign. Security was tightened in and around the city after Friday's attack. Police were manning checkpoints at all entry points to the city and were checking every vehicle, said a local government official, Sahibzada Mohammad Anis. – Agencies “Suddenly, a car exploded with a big bang,” said police official Malik Jehangir, who was at the checkpoint. – Agencies“There was a long queue of the vehicles. One of our officials wanted to search the car when it exploded.” Jehangir said 10 people were killed, including two police officials. Four children and a woman were among the dead civilians, he added.