Special Life Investigation Unit has seized the 4th suspect involved in the Karachi University bomb blast and initiated an interrogation from the other culprits linked to the incident here on Monday. At least 16 students were injured in a blast on Dec 28 at the Karachi University cafeteria in the campus. The bomb was planted under a tree near the cafeteria where there were many students were having lunch. As per media reports, 100 kgs of explosive material was used in the explosion at Karachi University. Special Life Investigation Unit has captured another suspect Ahsan of Jamia bomb blast from a shop pointed by the three already arrested suspects namely Umer, Faaiz, and Hafeezullah. During the investigation, these suspects, along with others, have confessed to plotting the bomb blast in the University. On the other hand, FIA has got the forensic report of the blast also. According to the sources, the explosive material that has been used in the blasts of Karachi University and Shikarpur, during Muharram-ul-Haram, is of same category.