One more person has been arrested for supplying arms to chartered accountant Amit Agarwal who used them to kill his mother-in-law before shooting himself at his in-laws’ house in Kankurgachhi on June 22, police said.

Prithwi Sagar, a resident of Nawada district in Bihar, is the second person to be arrested in connection with the arms supply to the deceased chartered accountant.

Sagar — who runs a gym, named Power Gym in Gondapur in Nawada — was picked up from his gym by a police team from Calcutta early on Wednesday. He has been brought back to the city, the police said.

The arrest comes a day after cops arrested Panjak Kumar, another Nawada resident, for supplying arms to Agarwal.

“Amit Agarwal had spent Rs 60,000 to buy the improvised gun he used to kill his mother-in-law before committing suicide,” an officer of the detective department said.

“Investigations have revealed that the lion’s share, comprising Rs 40,000 of the purchase money, went to Prithwi Sagar who supplied the gun to Pankaj Kumar. Kumar took Rs 20,000 for going to Calcutta and personally handing it over to Agarwal at Babughat in March,” the officer said.

Agarwal, 42, shot dead his mother-in-law Lalita Dhandhania and then himself at his in-laws’ flat in Kankurgachhi on June 22, hours after killing his estranged wife Shilpi in Bangalore and taking a flight to Calcutta, the police said.

His 70-year-old father-in-law Subhas Dhandhania ran out of the flat on seeing wife Lalita being shot dead and bolted the door from outside before alerting Phoolbagan police station, the police said.