At least three people were killed and 15 others injured in a massive explosion in the upper portion of a multi-storey building located at Maskan Chowrangi in Karachi's Gulshan-e-Iqbal, according to Pakistan's Geo News. 

Police and Rangers teams reached the spot soon after the incident and launched a rescue operation. The injured were shifted to a nearby hospital where the condition. 

(to be updated)