Calcutta, Dec. 1: Irshad Ansari, arrested on the suspicion of being an ISI agent, had helped a Pakistani national enter the Garden Reach Shipbuilders and Engineers' facility and film a warship of the Indian Navy being built there, Calcutta police special task force officers have said.

The Garden Reach Shipbuilders and Engineers (GRSE), which is under the ministry of defence, makes naval vessels.

Irshad, a resident of Garden Reach, was a peon in GRSE and had taken Mohammad Ijaz, later arrested by Uttar Pradesh police, twice to the ship-building facility, the STF sources said. The ship being made in 2014 was the INS Kadmatt, an anti-submarine vessel, the sources added.

"Ijaz, a Pakistani who had sneaked into Bengal two years ago, visited the site two times in 2014 when the vessel, which was handed over to the Indian Navy on November 26, was being built. He made video clippings of the vessel using his cellphone and sent them to Irshad's elder brother Irfan, settled in Karachi," said the officer.

The police officer said Ijaz got access to the GRSE site because Irshad had obtained a gate-pass for him.

The information was provided to this newspaper off the record, which means the officers mentioned in this report did not want to be named and cannot be held accountable for their statements. The claims made by the officers could not be independently verified by this newspaper.

STF sources said Irshad, son Ashfaq and brother-in-law Mohammad Jahangir were following the instructions of Irfan who had been recruited by the ISI 25 years ago. "Irfan, who left Calcutta in 1976, became a Pakistani national and a trusted man of the ISI after he planted several people as the spying agency's operatives in the city," an STF officer said.

Ijaz also got shelter in Irshad's house on the instructions of Irfan in Karachi, the sources said. The confession of Ijaz, arrested by Uttar Pradesh police last Friday, helped the STF trace the three members of the family here.

According to what Irshad supposedly told the police, the Ansaris were five brothers and five sisters. Two brothers - Iqbal and Irfan - are in Karachi and are Pakistani citizens. "In 1990, Irfan came in touch with an ISI handler, identified as Amir, who had information that Irfan had family in Calcutta. Amir lured Irfan, who was struggling to run his business, by promising to pay him money every month," the police source said.

"He (Irfan) came to Calcutta in 1995 to meet Irshad, who was working as a contract labourer in GRSE on a wage of Rs 119," said an STF officer. "He lured Irshad by offering him Rs 10,000 a month. Irshad agreed."

NIA officers visited Lalbazar and questioned the trio.