The Special Task Force of Calcutta police arrested an alleged operative of the Jamaat-ul Mujahideen Bangladesh (JMB), a banned Bangladeshi terror outfit, from Paikar in Birbhum in the early hours of Friday.

Najibullah, 50, was arrested from his home at Kashimnagar near Paikar after STF officers, who had been shadowing his activities for some time, got evidence of his alleged terror-related activities.

“Najibullah had a Facebook account in the name of Saqib Ali and used to spread radical ideas and hatred against non-Muslims,” said a senior STF officer. “He used to inspire youths to take the path of fundamentalism.”

Saqib, it now appears, is the name of one of Najibullah’s four sons.

Although it’s quite early into the interrogation stage, the sleuths believe Najibullah was part of the gang that was involved in serial blasts at Bodh Gaya, Bihar, in 2013. The police seized several electronic gadgets, including a laptop, a CPU, SIM cards and cellphones, from Najibullah’s possession.

The police though have made it clear they were yet to find out whether Najibullah had any IS connection or not, but the investigators said Najibullah’s JMB links appeared to be quite strong going by the types of books and other literature that were seized from a printing press that he used to run at his village.

Preliminary investigations revealed that Najibullah had finished his basic education at a madrasa in Uttar Pradesh and later worked as an imam of a mosque in Hiyatnagar in Birbhum district. Family members said he had left his work as the imam and started running the printing press.

Najibullah lives in a joint family with six brothers. He has four sons and three daughters. The eldest daughter is 16 years old and the youngest son is one-and-a-half year old.

“My father used to take orders for printing. A group of police officers turned up around 1.30am today (Friday) and took him into their custody. We still don’t know what his fault was,” said Sibgatullah , 15-year-old son of Najibullah.

He is a Class IX student at a local high school.

The arrest comes within a month of the National Investigation Agency picking up madrasa teacher Abul Momin Mondal from Raninagar in Murshidabad.

On Friday, NIA officials said they would want to interrogate Najibullah to find out whether he was present during the Khagragarh blast in Burdwan in 2014.

A JMB module was allegedly involved in the blast, the NIA said, and it was vital to find out whether Najibullah was a part of that same module.