TUMBLER RIDGE, B.C. -- A fast-moving wildfire in northeastern British Columbia is expected to double in size and is keeping about 200 oil-and-gas workers out of evacuated camps.

The Red Deer Creek fire southeast of the mining community of Tumbler Ridge was sparked by a lightning strike on Sunday, grew to 650 hectares on Tuesday, and now covers 5,000 hectares, or about 50 square kilometres.

The province's Wildfire Management Branch said Thursday that 80 firefighters are tackling the flames, using five helicopters and four air tankers.

Branch spokeswoman Jillian Kelsh said the provincial government is calling in more resources because the fire is expected to double due to hot, dry and windy conditions in the area where rain is not in the forecast.

"We'll have, hopefully, over 100 personnel on the fire tonight," she said, adding the branch is also sending firefighters to protect structures at the camps.

Flames were climbing to the tops of trees on Thursday, Kelsh said.

One of the biggest concerns is that the blaze may cross into Alberta.

A state of local emergency has been declared and an evacuation order issued by the Peace River Regional District remains posted on the regional government's website.

The order applies to oil-and-gas field areas of Ojay, Grizzly South and Red Deer Creek.