Four people were killed and 27 others sustained injuries when a blast ripped through a CD shop here in Peshawar at Nishtarabad area on Monday, a private TV reported. According to the report, the explosion occurred in a busy commercial CD market at Dasht Nagar area on G.T Road. Four persons have reportedly been killed and some 27 injured. Several shops also caught fire following the powerful blast. It happened soon after a bike rider left a CD shop in the market, an official on the spot said, adding that nature of the blast was being ascertained. The market is a distribution center of Pashto films and songs. The center was said to be under threat and has also been targeted by a suicide bomber last year. The explosion was heard far off in localities of the city, a frequent target of al Qaida and Taliban militants. Police and area people thronged to the spot and initiated rescue operations, shifting injured and dead bodies to Lady Reading hospital. Police put security cordon around the blast site. Score of fire fighters arrived at the scene in fire tenders and made hectic efforts to doze the blaze.