Customs and gardai yesterday seized cannabis resin with a street value of £3 million in a warehouse in south Co Dublin.
The joint Customs National Drugs Team (CNDT) and Garda National Drugs Unit (GNDU) raid discovered eight boxes with between 250 and 300 kg of cannabis resin.
Officers also found two firearms concealed in one of the boxes. The drugs and guns are being examined by forensic specialists.
No arrests were made following the seizure and the investigation is ongoing.
Welcoming the find, Senator Joe Costello said the fact that weapons had also been found "underlines the fact that drug gangs still represent a huge threat to dozens of communities across the country".
He said new drug gangs had moved to fill the gap caused by the flight or arrest of leading drug barons. "These gangs are reaping huge profits from their vile trade and the gardai and Customs services must be given every resource they need to combat these thugs."
He believed the Government should invest more in rehabilitation and drug prevention programmes. While the recent allocation of funding was welcome, hundreds of drug addicts could not get treatment places or support.
"To date the Government has failed to produce any new initiatives in our ongoing battle against drugs. This complacent attitude only serves to aid the drug gangs who continue to plague communities in Dublin and beyond," said the Labour senator.
He said the discovery of two bodies yesterday - which bore the hallmarks of "professional gangland hits" - underlined a continuing threat to society.