Central security agencies said that the banned Harkat-ul-Jehadi Islami militant outfit of Bangladesh was possibly behind the twin blasts in Hyderabad on Saturday in which 30 people were killed.
Sources said that there could be similarities between the explosives used in Mecca Masjid blast in Hyderabad in May this year and Satudrday's explosion.
It was suspected that Shahid and Bilal, who were the masterminds of the the Mecca Masjid blast were also behind Saturday's explosion.
Shahid is reported to be Karachi and is instrumental in bringing people for arms training from Hyderabad.
The Central Bureau of Investigation has already procured a red-corner notice from Interpol against Shahid.