The terror group Indian Mujahideen (IM) had earlier sent an email claiming responsibility of the Delhi blast. The investigating agency NIA, after a thorough search, claimed that the mail was being sent from Mamata Banerjee's state - West Bengal.
Meanwhile, police and the BSF have been put on alert in North 24 Parganas district following reports that five Bangladeshi terrorists belonging to Jamiyat-e-Mujahideen have entered West Bengal through Bagda.
After entering the state the terrorists have split up and headed for different areas, they said. They said that the names of the terrorists were available and they were trying to ascertain whether those were their real names.
Earlier Harkat-ul- Jehadi (HuJI) had claimed the responsibility of the blast. It has also been reported that HuJI had sent an email to a media house citing that this blast in the High Court was in retaliation to the death sentence pronounced on Afzal Guru, who has been convicted in the Parliament Attack case.