The Little Bobtail Lake fire southwest of Prince George has ballooned more than 40 per cent since Saturday, from 170 square kilometres to 240 square kilometres.
The increase was in large part thanks to unseasonably dry conditions in the region and heavy winds, with gusts peaking at 50 kilometres per hour, said Melissa Klassen, a fire information officer with the province's Wildfire Management Branch.
"We had 20-per-cent containment as of Saturday morning," she said, but by Sunday crews had lost part of that headway.
"The area that was looking really good, the area that we've made a lot of progress in over the last couple of days, unfortunately, is one of the areas where the fire broached the fire line."
More than 300 personnel are on the scene in the Little Bobtail Lake area, with 270 firefighters, 13 helicopters, 22 pieces of heavy equipment and eight air tankers brought in to battle the blaze.
The flames have forced the evacuation of about 80 people living around Norman Lake and Bobtail Lake, while neighbouring residents around Bednesti Lake and Cluculz Lake have been put on evacuation alert.
So far no buildings have been damaged.
The RCMP said they believe the fire was human caused and have pinpointed where the blaze began, though investigations are still underway to determine its exact cause.
Campfires were not banned in the area last Saturday when the fire broke out, though a prohibition on fireworks, tiki torches and grass burning had been imposed three days earlier.
The level of fire activity in B.C. this early in the year is "way above normal" and could herald a busier-than-usual fire season for 2015, said Klassen.
"We are seeing larger and more intense fires than usual," she said, adding that the flare-ups are more characteristic of fire activity in July and August.
"If we're this dry right now we're only going to continue getting drier."
The province's Wildfire Management Branch is on the scene of a half dozen other fires, most of which were sparked by lightning in the Cariboo region on Friday.
Many of those fires have been put out, though a small blaze near Pelican Lake, about 80 kilometres southwest of Quesnel, was 85-per-cent contained as of Sunday afternoon.
Another fire, about three square kilometres in size near the Chilako River southwest of Prince George, was reported on Sunday.
Cooler temperatures and lighter winds forecast for the coming days should offer some respite to fire crews.
The maximum penalty for starting a forest fire, as laid out in the province's Wildfire Act, is a $1-million fine and three years imprisonment.
A B.C. man was convicted of dropping the cigarette butt that caused a 2003 fire near Kamloops, B.C., which destroyed 60 homes and forced the evacuation of more than 7,000 people. He was eventually fined $3,000 for negligence.
— By Geordon Omand in Vancouver
— Follow @gwomand on Twitter
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