Two men have been arrested and drugs, firearms and ammunition seized in a series of raids in Central Otago and Queenstown Lakes.

Otago Lakes Central area commander Inspector Paula Enoka said nine search warrants in Cromwell, Alexandra, Clyde, Hawea, Wānaka and Queenstown were executed between Tuesday and yesterday as part of Operation Speargrass.

Methamphetamine, MDMA and cocaine were seized during the operation, along with eight firearms and thousands of rounds of ammunition.

Two men - aged 34 and 35 - have been arrested and remanded in custody on various drug supply, drug possession, and unlawful firearm possession charges.

A further four people - two males and two females - have had their firearms licences suspended as a result of insecure firearm storage and drug possession.

Insp Enoka said the operation was designed to disrupt the sources of illicit drugs in the community.

It was "extremely concerning'' to also locate firearms being improperly and dangerously held, she said.

"Holding a firearms licence is a responsibility that should not be taken lightly and it is vitally important firearms are kept in safe and secure storage.''

''Police will continue to target those who supply illicit drugs, which cause extreme harm and damage to our communities.''

"We can’t do this alone however, and we ask that anyone with information about the supply of illicit drugs contact us on 105.''

Information could also be reported to your local Police station or anonymously through Crime stoppers on 0800 555 111.