Patna Nov 14 (IANS): Four persons were critically injured after a powerful bomb exploded in Sultanpur locality under Danapur police station in Patna district on Sunday afternoon, police said.

ASP, Danapur, Sayyad Imran Masood, has visited the spot to investigate the matter.

"It is yet to ascertain where the bomb was kept. Due to the explosion, a section of two buildings which are adjoining to each other collapsed. Four persons were critically injured in the incident," Masood said.

The explosion occurred in a house belonging to Mohamad Shafiq, a contractor in Danapur army cantonment and Mohamad Own. Due to the powerful blast, the adjoining wall of two's houses came down, while the widow glasses of the adjoining apartment were also shattered.

The injured were identified as Shafiq's son Shahid Abdullah, wife Aayesha Khatoon, mother Sabadrina, and Jayeda Khatoon. All of them are initially admitted in sub-divisional hospital Danapur and later on shifted to Patna Medical College and hospital (PMCH) as their condition was critical.

Sources have said that the bomb was kept in Shafiq's house, which was damaged more, and the casualties were from his family. The investigation is on to find out whether this incident has any connection with work at Danapur cantonment.