MEDFORD (AP) — When a burglar broke into a Medford pharmacy this week, looking to snatch some drug, he was foiled by fog.

The dense fog, a new technology offered by alarm companies, made it impossible for the robber to find the sought-after narcotics.

Pharmacy break-ins are prevalent throughout Oregon. And now drugstore owners are stepping up efforts to protect their businesses, using everything from grates over windows and doors to alarms and surveillance cameras.

The fog protection is the latest twist. It adapts fog machine technology used in entertainment to create an extremely fast-spreading, long-lasting, dense fog that is triggered by motion detectors or other sensors.

The fog, made by combining water and glycol, has a “soft mint smell,” can fill a room in three to five seconds, and blocks visibility for at least 10 minutes. It can last up to an hour or be removed in about 15 minutes with ventilation and doesn’t leave a residue, according to manufacturers.

In the Medford case, police arrived two minutes after the alarm was triggered to find the shop filled with fog and no suspects around.

When the fog cleared and a pharmacist checked the inventory, only “a few bottles of cough syrup were gone,” said Detective Sgt. Mike Budreau said.

That’s a far cry from the thousands of prescription painkillers that have been stolen in past pharmacy burglaries.

Highly physically addictive pain medication such as oxycodone and hydrocodone are often targeted in the crimes, authorities said.

State law requires controlled substances at pharmacies be secure, but doesn’t list specific security requirements.

However, Gary Miner, compliance director at the state Board of Pharmacy, said his inspectors increasingly see sophisticated security measures at pharmacies.