Kolkata: At least 15 neo Jamaat-ul- Mujahideen Bangladesh (JMB) operatives have entered West Bengal from the neighbouring country earlier this year and 10 of them moved to various parts of India including Jammu and Kashmir, an officer of Kolkata Police's Special Task Force (STF) said on Monday.

The remaining five had stayed back in West Bengal and three of them, who are Bangladeshi nationals, were arrested from south Kolkata's Haridevpur area on Sunday, the officer said.

It was revealed during interrogation of the three persons that 10 suspected JMB operatives have gone to Odisha, Bihar and Jammu and Kashmir, the IPS officer said.

The other two, who had stayed back in the state, were Sheikh Sakil and Salim Munshi, and the STF is looking for them.

'Sakil had helped them (the three others) in preparing fake Aadhaar cards which they had used to get accommodation on rent in Haridevpur. The three came to India following the instructions of senior JMB leader Al Ameen,' he said.

The three - Najiur Rahman, Rabiul Islam and Sabir -- used to sell fruits and mosquito curtains for a living.

The STF has contacted the Bangladesh Police to know details of the arrested trio, the officer said, adding that the landlord of the house of which they had taken two rooms on rent was called for questioning.

'We need to know how he came to know these persons, he said.

The National Investigation Agency (NIA) on Monday also started collecting information about the three arrested JMB operatives.

'We have started gathering information about them and trying to find out who else are associated with them. We are at a very initial stage,' an NIA officer said.

Meanwhile, when produced before a city court, the three suspected operatives of the Bangladesh-based banned outfit were remanded to 14 days' police custody.

Several documents, including jihadi materials, lists of top JMB leaders and their associates in other terror groups were seized from their possession.

A number of JMB operatives including Indians were arrested from West Bengal in the past few years.

The JMB, which carried out a terror attack at a popular café in Dhaka in 2016 in which 22 people including 17 foreigners were killed, is trying to spread its tentacles in India, the NIA had said in 2019.