Three young men and a woman were arrested by the Salt Lake police for allegedly posing as shoppers at a mall and swapping the tags on high-value garments with those on less expensive ones so they could buy the pricier clothes at a lower cost.

The Bidhannagar police received a complaint from an outlet of Smart Bazar in Salt Lake on Thursday that the mall staff apprehended four “shoppers” who allegedly tampered with the apparel tags.

The mall authorities told the police that the four were caught at the billing counter when the price of an item mentioned on the tag did not match the figure recorded in the system.

“An employee at the billing counter became suspicious when he found that the price mentioned on the tag of a garment did not match their record in the computer,” said an officer of Bidhannagar (South) police station where a complaint was lodged.

The employee reported it to the mall manager and on checking all the garments the four had selected, they found that the tags of all had been replaced, the officer said.

The four — aged between 21 and 23 years — initially claimed innocence. They were handed to the police.

The police identified the accused as Maloth Jagdish, 21, Kailash Suryawanshi, 23, Vijay Sakhare, 23, and Suchitra Rana, 22.

“On being questioned by our officers, the four admitted to the crime and said they had done this before,” said an officer of the Bidhannagar Police Commissionerate.

“They would choose an expensive garment and a relatively cheaper one. Then they will go to the changing room and swap the tags. They said they got away with this a few times and purchased high-value clothes at much lower prices. We are yet to verify their statements,” the officer said.

The police said two of the accused are students at a homoeopathy institute in Calcutta and the other two study at a city-based pharmacy college.

“They are from Maharashtra, Telangana and Dadra and Nagar Haveli,” the officer said.

The police have asked for CCTV footage from the mall.

“The footage would be helpful to find out which clothes they picked from the racks and took to the changing rooms. Their tags can be examined to establish the alleged crime,” the officer said.

The four have been booked under the charge of cheating.