A man who was arrested near chief minister Mamata Banerjee’s home on July 21 was allegedly in contact with several senior GST officials and used to provide information based on which the central agency would conduct raids, the chief public prosecutor submitted before a court on Thursday.

Sheikh Noor Amin, 35, was picked up while he was allegedly trying to break through the security cordon to meet the chief minister.

Chief public prosecutor Sourin Ghosal said at the court of the chief judicial magistrate in Alipore on Thursday that Amin was in “close touch” with some GST officials and used to hold meetings with them at several star hotels in the city.

“During the investigation, it has been found that Amin used to collect information about companies that default on GST and based on the information that he shared with some top GST officials, the central agency has been able to conduct successful raids and recover the taxes,” Ghosal said.

Ghosal added that as a reward for his work, the central agency had paid him Rs 18 lakh. “A copy of that reward letter has been found in his house. It has been submitted before the court,” Ghosal said.

Amin, a resident of Anandapur off EM Bypass, was arrested when he was headed towards Mamata's Harish Chatterjee Street home in a car allegedly carrying a gun, a dagger and some drugs sometime before the chief minister was scheduled to leave for the Martrys’ Day programme at Esplanade on July 21.

Ghosal submitted in court that based on the information shared by Amin, the police had arrested another person who allegedly helped him procure forged identity cards from state and central agencies.

The chief public prosecutor said that though Amin’s defence lawyer said his client was mentally “unstable”, the prayer was challenged by the submission of the “reward letter”.

“There is no question of the accused being mentally unstable. His links with some of the top GST officials are well-established. One of them is at present posted in Chennai,” Ghosal said.

The court heard the prayers of both sides and sent Amin to judicial remand till August 17. The second person who has been arrested in this case has been remanded in police custody.

Amin was also carrying two identity cards — one saying Border Security Force and another All India Police (IB) — the police had said after his arrest. The vehicle Amin was driving had a board with “police” written on it.