Kolkata: In a major breakthrough, the Kolkata Police's Special Task Force on Tuesday arrested three suspected terrorists from the city's Railway Station.

They were arrested following a tip-off about their presence by the central intelligence agencies, according to reports.

The STF also recovered several documents related to world's dreaded terrorist outfit al-Qaeda from them.

#Visuals from Kolkata: 3 suspected terrorists arrested by Bengal state STF from Kolkata railway station, documents related to Al-Qaeda recovered from them. pic.twitter.com/0bGr5nFNsf — ANI (@ANI) November 21, 2017

They are believed to be the members of the Bangladesh-based Islamist outfit Ansarullah Bangla Team (ABT), which is involved in the murder of lots of (Bangladesh) bloggers. The organisation has been banned in Bangladesh, Murlidhar Sharma, DC STF, Kolkata Police, said.

We had received credible input on them by the Central Intelligence Bureau, Sharma said while addressing a press briefing.

Initial investigation by the police suggested that the two of the three men are Bangladeshi nationals who had illegally entered India to buy modern firearms.

They had been living illegally in India for the last one and a half years, he added.

The third man arrested by the Special Task Force of Kolkata Police is a local arms dealer.

"The three were arrested by the STF around 2.30 pm, including Shamsad Mia alias Tanveer alias Tushar Biswas and Riaz alias Riazul Islam from Bangladesh," the officer said.

"Manotosh Dey alias Mona Da is suspected to be an arms dealer from North 24 ParganaS district's Basirhat. Laptops, pen drives and firearms, including a revolver and a shot gun, and several incriminating documents have been seized from the three," he said.

The ABT is a front for al Qaeda in the Indian subcontinent and is banned in Bangladesh.