Suspected terrorist Chatal Magsi revealed this information before the investigators during detention.
He also provided other leads to law enforcers that may unleash anti-terror operation in the identified areas to bust network of proscribed terror outfits.
Recently, security sources disclosed that Hafiz Qasim Rasheed Group of outlawed Lashkar-e-Jhangvi was operating in the metropolis.
Hafiz Qasim Rasheed alias Ganja, presently imprisoned in Sukkur Central Jail, has been the chief of the Sindh chapter of (LeJ). He is believed to be operating his terror network from the jail.
According to security sources, scores of the operatives of the terrorist group have been released from Sukkur Jail. The members of the group could commit incidents of terrorism again, the officials feared.
Five people were killed at Shafeeq More and Nagan Chowrangi areas of the city this month, leading investigators to unearth Qasim Rasheed.
On December 1, 2015, gunmen had killed two soldiers in the city in a rare attack on the army that could indicate the beginning of a push-back against a tightening crackdown on violence.
The two were shot on a busy road in Saddar area, a centre of Karachi.