Police say thieves put people's lives at risk by taking critical medical supplies from a rescue helicopter in Otago.

The Queenstown rescue helicopter was burgled at the Taieri Airfield over the weekend after taking a critically ill patient to Dunedin Hospital.

The helicopter's medical supply stores were raided and a bag containing medicine and other items was taken.

Helicopters Otago chief executive Graeme Gale said bad weather prevented the crew from flying back so they were forced to hold over in base.

"If the helicopter and crew had responded to an incident unaware that the bag had been taken, there could have been fatal consequences," he said.

Acting area investigations manager Detective Sergeant Hayden Smale said an investigation was under way and anyone with information should contact police.

"Beyond putting the lives of air ambulance patients at risk by taking these essential medical supplies," he said.

"We urge extreme caution for anyone who may come into contact with these stolen medical supplies."

Police would like to hear from anyone who might have information about the burglary, or those involved.