National Security Advisor (NSA) Shivshankar Menon and other senior officials in the security establishment attended the meeting, sources said.
Union Home Secretary R K Singh, who visited the Ram Manohar Lohia Hospital where most of the injured in the blast have been admitted, said, "We have received initial forensic reports. We are waiting for some more."
Chidambaram had last night said that a detailed forensic report carrying "critical evidence" was expected today which could throw some light on the probe of the blast being spearheaded by the NIA.
The toll in the blast rose to 12 this morning while the condition of four of the victims continued to be critical.