Kolkata, Nov 12 : The investigators reached Nabagram in Murshidabad on Wednesday. According to sources, the NIA came to Bengal after getting certain phone numbers from the suspects who were arrested in connection with the Delhi blast.

Sources said the operation began at 7 a.m. at a village under Nabagram police station in Murshidabad. The NIA investigation team went to the house of a person named Mainul Hasan. He was called and questioned for a long time. It is learnt that Mainul Hasan is a migrant worker by profession. He had worked as a migrant worker in Delhi and sometimes in Mumbai.

Sources said that Mainul had contact with members of some militant organisations at that time.

Sources said that Mainul's phone number was received from one of the suspects of the Delhi blast.

A search was also conducted at Mainul's house. Apart from Mainul's house, the investigating officers are roaming around Murshidabad villages and making enquiries.

Sources said that apart from Mainul, several other names have come to the fore. The operation is being conducted based on such names. It is being investigated whether these residents of Murshidabad are directly or indirectly involved in the Delhi blast. The neighbours of the area were surprised by this sudden operation.

At least eight people were killed and dozens were injured after a blast in a car near the Red Fort on Monday evening.

The blast took place in a Hyundai i20 car at 6.52 p.m. near the Red Fort Metro Station, leaving mangled bodies and damaged cars scattered in the busy area.

A high alert has been sounded in Delhi. The Delhi Police have invoked UAPA (Unlawful Activities Prevention Act) sections after forensic evidence and intelligence inputs pointed to possible terror links.

The investigators have arrested about 15 people in connection with the incident and are searching for others who were directly or indirectly involved in the blast.

/IANS