The CBI on Saturday told a local court that Sharad Kalaskar, one of the accused in the killing of rationalist Narendra Dabholkar, disposed four firearms in a creek near Mumbai in July this year.
The agency has claimed that Kalaskar was one of the two persons who shot Dabholkar on August 20, 2013, on the Omkareshwar Bridge in Pune.
The Central Bureau of Investigation (CBI) also told the court that Vaibhav Raut, arrested by Maharashtra Anti-Terrorism Squad (ATS) in the arms haul case in August, was with Kalaskar when he dumped the weapons.
The duo was arrested on August 10 by the ATS following a raid in Nallasopara area of Palghar district in which explosives and firearms were seized.
The court of Judicial Magistrate S M A Sayyad extended Kalaskar's custody till September 17.
CBI lawyer Vijaykumar Dhakane told the court that on July 23 this year, Kalaskar and Raut, dismantled four firearms and dumped them in a creek from a bridge while going from Pune to Nallasopara in Palghar, near Mumbai.
Dhakane said the agency was yet to ascertain the location of the bridge from where the weapons were disposed of.
"As they were travelling at night, the suspect cannot recollect whether it was Kalva, Ghodbunder or any other bridge from where he had thrown the firearms," Dhakane told the court.
Meanwhile, a CBI officer said the agency suspects that one of the four weapons dumped in the creek was used in Dabholkar's killing.
He said Kalaskar and Raut may have decided to dispose of the weapons after developing cold feet following the arrest of Amol Kale in connection with the killing of journalist-activist Gauri Lankesh.
Kale was arrested in May this year by Karnataka police's special investigation team, which is probing Gauri's murder.
The CBI took custody of Kale earlier this month in connection with Dabholkar's killing.