At least four people were injured when a bomb exploded in a passenger bus in Sheerin Jinnah Colony in the metropolis on Tuesday, says in media reports. As per the initial reports, the bomb exploded in a passenger bus near Sheerin Jinnah Colony, wounding at least four people. Soon after the blast, the area residents shifted the wounded people to local hospital for medical assistance. The South Zone police officials confirmed the blast was occurred due to explosive material as no piece of the gas cylinder was recovered from the blast site. The police officials said that the explosive material was likely to be planted at the gate of the bus terminal. The Bomb Disposal Squad (BDS) has also been called in to ascertain the nature of the explosion.