A remote controlled bomb at a television network office in Karachi has killed three people and wounded five others, officials said Friday.The explosive device, which went off late Thursday, was planted in a bag near the gate of the cable network operator's office in a poor area in the east of the city, police said."Somebody put a bag filled with explosives near the gate of the cable operator's office and exploded it through remote control," senior police official Naeem Baroka told AFP. "Three people were killed and five others wounded."Another police official, Raja Umer Khitab, said two kilograms of explosives were used. "Two shops near the cable operator office were also damaged by the impact," he said.Hospital officials confirmed the death toll. "We received three dead bodies and five wounded from the cable operator blast site," doctor Seemi Jamali of Jinnah Hospital told AFP. Recent violence in Karachi has fuelled fears of instability as the country heads towards general elections in May.The city of 18 million, which is Pakistan's business hub, last year saw around 2,000 people killed in violence linked to ethnic and political tensions, its deadliest toll in two decades.Earlier Thursday Karachi police said they had shot dead a Tehrik-e-Taliban militant commander suspected over the killing of a prominent woman development worker.Parveen Rehman, 56, who was known for her work in impoverished neighbourhoods, was killed by motorcycle gunmen in the city as she drove home from work Wednesday.Police also said they had Thursday arrested six Taliban militants from the city's southern and western neighbourhoods and seized explosives and weapons."Those arrested included Bashir Ullah, who was a mastermind of the deadly bombing in Abbas Town neighbourhood," senior police official Shahid Hayat said, referring to the explosion in the Shiite neighbourhood on March 3 that killed 50 people.