As many as eight activists of the banned Students Islamic Movement of India were rounded up by the police in connection with Monday night's bomb blast in Modasa town's crowded Sukabazar area, in which one person was killed and eight others injured.

Modasa Deputy Superintendent of Police K K Mysorewala told UNI that the bomb was placed in a parked motorcycle in a congested and crowded area of the town, which went off at around 2130 hours.

The bomb was with a timer device. The number plate on the motorbike was a fake one. Even its chassis number was also tampered with.

Mysorewala said the forensic experts had collected samples from the site, and the report is expected to provide some vital clues about the blast.

Officials of Anti-Terrorist Squad and Ahmedabad [Images] crime branch sleuths had visited Modasa town late on Monday night.

Meanwhile, the government has put the entire state on high alert following the Modasa blast and that the Navratri festival, the longest dance festival in the world, is commencing from Tuesday evning in Gujarat.

Authorities have made elaborate security arrangements to ensure that Navratri festival passes off without any untoward incident.

Gujarat Home Minister Amit Shah has reiterated the ruling Bharatiya Janata Party's demand for the Centre's nod for Gujarat Control of Organised Crime Bill.