Smoke is seen rising on Saturday from a forest fire in Glenrosa in B.C.'s Okanagan region. (Submitted by Eric Lee)

About 5,000 residents were forced to flee their homes Saturday as fire crews battled a quick-spreading forest fire covering two square kilometres of West Kelowna, in B.C.'s Okanagan region.

Three homes have been destroyed and 12 others were deemed under serious threat in the Glenrosa area. A further 1,500 homes near the blaze have been evacuated, fire officials said.

B.C.'s Okanagan region has been plagued by forest fires in the past. (CBC)

The evacuation zone includes Upper and Lower Glenrosa, and the Seclusion Bay, Gellatly Bay, Goat's Peak and Horizons areas.

Police were going door to door in Gellatly Bay to urge residents to leave.

The large Gorman Brothers sawmill was also threatened.

B.C. Forestry sent six helicopters, eight aerial water bombers, 45 firefighters and two water trucks to assist the Kelowna and Peachland fire departments in battling the blaze.

Three groups of tanker aircraft were to continue to work the fire until dark, laying fire retardant to slow the spread of the fire, forestry officials said.

Strong, hot winds gusting to 50 km/h and extremely dry conditions were hampering efforts to contain the blaze and were expected to continue late into the night, officials said.

"Our first concern is for public safety and the safety of our emergency personnel," said Kirsten Jones, who speaks for the District of West Kelowna.

Residents in the affected areas were asked to report to emergency evacuation reception centres at Royal LePage Place, at 2760 Cameron Rd., and Mount Boucherie Secondary School, at 2751 Cameron Rd.

The fire crossed Highway 97, which was closed northbound at Drought Road and southbound near Hubert Road.

Concerned residents or relatives can call 1-250-469-8490. Residents who are unable to reach evacuation centres are asked to call 778-797-2269.

Sun 'blotted out': Day

International Trade Minister Stockwell Day, who represents the West Kelowna constituency where the fire is raging, said he was getting briefings from emergency crews.

"I can see the flames, and the winds are very strong," he said early Saturday evening. "The sun was blotted out for quite a while earlier in the afternoon."

Day said that the highway leading out of the area was jammed with people taking pictures and trying to leave.

Elise Riedlinger, a Kamloops fire centre information officer, said they were alerted to the blaze just before 3 p.m. Saturday.

According to the BC Hydro website, more than 1,500 customers are without power because of the fire. Power is also out in nearby Peachland.

In 2003, a wildfire in Kelowna forced the evacuation of approximately 45,000 residents and destroyed more than 230 homes. The final size of the fire was estimated at 25,000 hectares.

With files from The Canadian Press