Investigators probing on Wednesday's bomb blasts in Mumbai which killed at least 17 and injured 131 are zeroing in on the likely involvement of the Indian Mujahideen, a domestic terrorist group.
Police confirmed the explosive devices used were crude home-made bombs hidden in traditional steel lunch-boxes and were left in public
places, which they say is a trademark of group responsible for several other attacks in various Indian cities in recent years.
In February last year, the Indian Mujahideen (IM) were responsible for an attack in the western city of Pune and in 2008, they also struck in Delhi.
Investigators say they believe the group intends to strike on the 13th or 26th of the month, a pattern that dates back to 13 May 2008 when the
group targeted Jaipur.
However, despite the investigators' suspicions, so far nobody has claimed responsibility for the attacks, which also left at least 131 injured.