Trick-or-treaters in the northern Manitoba town of Churchill will get street protection worthy of a visiting head of state this Halloween.

Come Sunday night, the town of 1,000 will be ringed by about a dozen fire trucks and ambulances, all revving engines and shining spotlights on goblin-filled streets to keep curious polar bears from getting a little too close to roaming children.

Overhead, a helicopter will circle, while a crew armed with immobilizing darts will be stationed around town, just in case the bears don't get the point.

Halloween's polar bear patrol has been a feature of Churchill for 20 years. Bears are regularly spotted in the community from early summer to the end of November, depending on ice conditions. They lope into town because of Churchill's proximity to the world's largest denning area.

Firecrackers and high-pitched whistles await the boldest of bears, who manage to skirt the blaring engines and blinding lights to enter the town.

And if they still persist, there's bear jail.

Repeat trespassers are corralled into a cell and kept for about a month, which conservation experts believe is enough time to isolate bears and break them of their pattern of wandering into town.

Last year, 151 bears filled the cells to capacity. Another 25 bears had to be flown out because the compound was full.