Inter

ISLAMABAD, Pakistan An explosion on a rail line killed three people Friday in northwestern Pakistan, rescue workers said.

ra Pakistan's capital was rocked by a suicide attack on the city's Marriott Hotel at the weekend.

A bomb left on the tracks exploded as a train passed by, derailing it, police said. The blast killed a woman and two children and wounded 12 people, at least three critically, according to police. The blast happened about 2 p.m. (4:30 a.m. ET) near the Boys Degree College in Hasil Pur in the Bahawl Pur District, police said. The train was on the way to Samasatta in Punjab province to Bahawl Nagar. Pakistan has been on edge since a suicide bomber killed 50 and wounded more than 250 at the Marriott Hotel in Islamabad on Saturday. Earlier Friday, four suspected terrorists died during a raid in the southern port city of Karachi, police said. The men were in a shootout with authorities when they detonated explosives in the Baltia Town section of Karachi. Intelligence information suggested militant organizations might target locations in Karachi.

As a result, police launched two raids on Friday.