An underground bunker with a battery-operated lift, 234 cannabis plants, two homemade firearms and a sawn-off shotgun were amongst discoveries made by police during raids in Adelaide's north-east.

The raids of 15 properties were part of Operation Falcon, which targets cannabis growers.

Police said final figures were yet to be tallied, but in addition to the cannabis, they also seized more than $6,500 in cash and a range of equipment used to hydroponically grow the drug.

The removal of floorboards revealed a secret drug bunker. ( Supplied: SA Police )

Electricity had been diverted at five properties and at one address in Para Hills police located 84 plants.

Eight people have been arrested and three reported.

Superintendent Guy Buckley said the targeted properties were identified following investigations and tip offs from the public to Crime Stoppers.

Superintendent Buckley said police would continue to target drug offenders.

"Cannabis use is of concern to SA Police and is not accepted, or acceptable at any level," he said.

He urged anyone in with information regarding illicit drugs in the community to contact Crime Stoppers on 1800 333 000.

All information can be provided anonymously.