The police on Tuesday busted a racket in which touts, posing as ‘inspectors’ of the state health department, invaded pathological laboratories and nursing homes to blackmail the owners.

Deputy commissioner of police (north) P. Ravi said the lid was ripped off with the arrest of Mrinal Dasgupta from a north Calcutta laboratory. Dasgupta was carrying a forged identity card of the health department. He turned up at a laboratory on Bhupen Bose Avenue on Tuesday afternoon and told the employees his department had sent him to investigate complaints against the laboratory. After some time, he began to talk money. Lab director Shankar Banerjee called up the health department to unmask the fraud.