Home Minister P. Chidambaram on Friday said there were "promising" but no conclusive leads in the Delhi high court blast so far but investigators have taken into custody the person suspected to have sent the e-mail from Jammu and Kashmir owning responsibility for the terror attack.
"There are promising leads but I cannot call them conclusive leads. They are being pursued round the clock," Chidambaram told reporters about the progress of the probe into the bombing that killed 13 people and injured over 90 others.
He said the forensic experts were corroborating their findings about the nature of the explosives used in the powerful bomb that exploded outside the Delhi high court on a busy Wednesday.
Union home minister P Chidambaram arrives at Delhi high court bomb blast site in New Delhi.
"Preliminary findings of forensic experts indicate nitrate-based explosives were used.
"These findings are being reconciled to know the exact nature of the explosives," the minister said, indicating that investigators were yet to make any major headway in cracking the third worst attack in India since the November 2008 Mumbai strike.
He said the investigators have traced the e-mail attributed to the Harkat-ul-Jehadi Islami (HuJI) to an internet cafe in Jammu and Kashmir's Kishtwar district.
"The person suspected of sending the e-mail has been taken into custody for interrogation. We will have to wait for the report (after questioning of the suspect)," Chidambaram said.