Three persons have been arrested in Bihar by the Crime Branch-Criminal Investigation Department (CB-CID) of Tamil Nadu on the charge of supplying a country-made pistol to the Panayur double-murder case accused, who died in police custody.

The arrest followed investigations into mobile phone numbers found during searches at the house of the accused Shanmugasundaram alias Rajan. One of the phone numbers was traced to Bihar, police sources said. It was also found that Rajan had visited Munger district in Bihar a few months back.

A CB-CID team with the help of Munger police arrested Mohammed Pallu (33), Dev Sundar Kumar (20) and his brother Neeraj Kumar Neerala (18), alleged arms traders in Kalyanchuk village.

During interrogation, the trio confessed they had supplied arms to Shanmugasundaram, the pistol used by him for murdering retired ship captain Elangovan and his wife Ramani in their bungalow at Panayur on the city outskirts on August 24.

The three were brought to Chennai by train this morning and produced before Alandur Magistrate Court, which remanded them to judicial custody.

The case, initially investigated by local police, was handed over to CB-CID after various theories, including alleged political link, surfaced following the sudden death of Shanmugasundaram in police custody.

Though initially police suspected that land dispute might have been reason for the killing, CB-CID ruled out land dispute and also rejected the theory of possible involvement of some politicians in the crime.