Police have registered a case and investigation has been taken up, the official said.
He said the security forces recovered one AK rifle with two magazines, one M4 US carbine with three magazines and six Chinese pistols.
Sukma and Kanker are among the seven districts in Bastar zone, south Chhattisgarh, that remain among the worst affected by the presence of Maoists.
The operation was launched after receiving intelligence inputs in which multiple teams of Indian Army and Assam Police conducted extensive search operations in Kokrajhar and Udalguri districts.
The other two injured labourers identified as Fida Hussain and Shabir Ahmad have been rushed to a hospital.
It was the first response from the CM ever since the CAG report levelled damaging allegations against the police department under him, on February 12.
An FIR has been registered in Poonch Police station under relevant sections of law and investigation taken up.
As an accident had taken place with this ammunition "K" at Gopalpur firing range in November 2014, the AHQ had asked the OFB to stop its production.