West Bengal’s Criminal Investigation Department has arrested 42 people for allegedly cheating in the state police constable recruitment examination held on Sunday, IANS reported.

“We had information that candidates in different examination centres will be using improvised wireless devices, comprising a receiver in the shape of a credit card and an earphone, during Sunday’s preliminary test for constable recruitment,” an unidentified officer of the department told PTI.

Deputy Inspector General of West Bengal CID Nishad Parvez said devices were found hidden in the shoes of candidates and “wirelessly connected to mobile phones which were being operated from outside to supply them with necessary information”.

Parvez said the department has lodged 28 cases and are trying to track others involved in the racket.

In June, the Uttar Pradesh Special Task Force arrested 16 people in connection with cheating during the Uttar Pradesh Police Constable Recruitment examination.

In Rajasthan, mobile internet services were suspended in July during the police constable recruitment examination to ensure there was no cheating. The recruitment examination was cancelled in March, when it was held online for the first time, after a Special Operations Group busted a “hi-tech real-time cheating racket”.