A woman has been arrested and drugs, ammunition and firearms have been seized following search warrants in Central Otago.

Three warrants were executed in Alexandra and Cromwell yesterday (June 22) in relation to the supply of methamphetamine by people linked to organised crime groups in Christchurch and Invercargill.

Sergeant Derek Ealson said that at two of the Alexandra addresses police located methamphetamine, items used in the supply of methamphetamine, meth utensils, ammunition, and a firearm.

A 37-year-old local woman is due to appear in Alexandra District Court on June 29 on methamphetamine and firearms charges.

"Enquiries are continuing and further arrests are likely," Sergeant Ealson said.

"Police take our role in preventing the harm caused by illicit drugs incredibly seriously, and work incredibly hard to hold offenders to account."

Derek said those suffering from drug use will be referred, where appropriate, to agencies that can help.

If you, or someone you know, is experiencing harm from drug use or addiction, contact the Drug and Alcohol Helpline.