Carbine is a type of gun used only by the defence and para-military force in the country.
"Forensic examination revealed that the carbine seized from Dhalasamanta brothers was manufactured at Indian Ordnance Factory, Kolkata. We will send a team to Kolkata to further investigate the matter," Commissioner of Police Y B Khurania told reporters here.
"We will soon get to know all the details about the carbine," Khurania said.
The police was worried over recovery of weapon like carbine from the residence of Sushil Kumar and Sushant Dhalasamanta on January 30.
The police have seized one carbine, one double-barrel gun and four mousers and 150 rounds of ammunition during searches conducted in their houses at Bhubaneswar and Cuttack.
It was earlier believed that the weapons seized from the brothers, who have nearly two dozen criminal cases pending against them at various police stations of Odisha, were procured from a don of Uttar Pradesh since they had admitted their links with him during interrogation.