Traffic was stopped on a busy Vancouver Island highway as crews battled a nearby wildfire that broke out in Mill Bay.

The fire, called in as a brush fire roughly around 1 p.m., was initially estimated to be about half a hectare in size but has since grown to 1.5 hectares.

Officials said it originated around Trowsse Road near Bamberton Provincial park.

Four fire departments responded to the blaze including crews from Mill Bay, Malahat, Cowichan Bay and Shawnigan Lake.

"We're tired. We've been here probably four or five hours and it's starting to show its toll," Mill Bay Fire Chief Ron Beck said.

Beck said about 40 people in total were looking after the blaze, and it took some time to get manpower to the scene.

The Coastal Fire Centre said it assisted with an attack crew of 26 firefighters, two officers and two helicopters.

The fire appeared to be under control at one point, but flared up again and moved dangerously close to the Trans-Canada Highway.

Smoke plumes could be seen on either side of the highway and the Coastal Fire Centre confirmed embers had sparked another fire on the other side of the busy route.

Just after 6 p.m., Beck said there was still a "very sufficient" fire still burning on the west side of the highway.

He said crews would likely remain there throughout the night and into Friday morning, mopping up and extinguishing hot spots.

Northbound traffic was halted on the busy route as crews dealt with the fire and being rerouted through Shawnigan Lake.

Smoke could be seen from around the South Island.

Beck said it's the second time a fire has broken out in the area, and a cause is still under investigation.

Northbound traffic still closed on Highway One as crews battle 1.5-hectare blaze. Traffic being diverted through Shawnigan. — CTV News VI (@CTVNewsVI) August 25, 2016