The secret operation codenamed 'Operation Thunderstorm' resulted in the seizure of the heroin consignment from Hasth Kalan village in Punjab's Firozpur district.
Two pistols (a Pakistani make and a Chinese make), 52 live cartridges and three magazines were also seized from one Khan Singh alias Khan, DRI sources said.
"The recovery of arms and ammunition points to a bigger conspiracy, which is being investigated by DRI. This is one of the biggest seizures of heroin made by any agency in recent times. The earlier seizure of 75 kg heroin was also made by the officers of DRI in April this year," the agency said in a statement.
It said DRI has launched a massive country-wide drive against the drug smugglers and have achieved significant success in recent times.
Under the 'Operation Thunderstorm', launched in June this year, the DRI has seized drugs worth nearly Rs 500 crore, which includes 17 tonnes of cannabis, 1,500 kg of ketamine, 500 kg of hashish and other synthetic drugs.
"This drive against the drug smugglers will continue as they pose grave danger to national security and society at large," DRI Director R S Sidhu said in a statement.