4 policemen were killed in Jammu and Kashmir's Sopore town on Saturday in an improvised explosive device blast. The attack targeted a patrol unit of the police in the main market in Sopore. 3 shops were also destroyed in the massive explosion. No terror group has claimed responsibility for the attack so far. The place was cordoned off and a search operation is underway, a police officer told news agency IANS. Shops in the market were closed and the area was largely deserted due to a strike called by separatists over the 1993 massacre in which 57 people were killed in firing by security forces.