Brian Lush of Stephenville went missing in Ontario. His family and police are looking for help

It has been nearly a week since Brian Lushdisappeared somewhere in Ontario.

He was last seen at a gas station inSummerstown, southeast of Ottawa, around 4:30 p.m. ETon Wednesday.

That's where his commercial transport truck was foundalong with his personal belongings, but there hasn't been atrace of the 51-year-old man from Stephenville, N.L., since.

"On surveillance video, right after 4:30 p.m., we see him get out of his truck, he walks around the front of thetruck and then he walks out of camera range,"Bill Dickson, media relations co-ordinator of the Ontario Provincial Police'sEast Region, told CBC News on Tuesday.

"He was never seen again, as far as we know."

His brother, Craig Lush, calls the situationdifficult and very unusual.

Lush told CBC News his brother always remains in contact with his family and was headed east to Newfoundland.

"We never would have thought this would happen. To walk away from his truck is highly unusual, and then to go without making contact for a long period of time is something that he has never done in the past," he said.

"We're holding it together. There's a lot of us. There's a large circle of family and friends in Newfoundland, Nova Scotia across the country, really."

The OPPis searching for Brian Lush and isasking the public for dashcam video from Highway 401 westbound, in the Boundary Road area near Cornwall, from Thursdaybetween 10:30 a.m. ET and noon.

Dickson said there may have been a few potential sightings since Wednesday, but they're mostly partial matches of Lush's clothing description along the highway and on a trail.

The OPP is also asking hunters or others with trail cameras in the South Glengarry, South Stormont and Cornwall area to check for any possible sightings.

"We don't know where he is. We don't know why he wandered away from his truck. He left his personal belongings, the keys were left in the truck, and from what we hear this is very out of character for him," Dickson said.

"We've been assigning as many resources as possible."

Those resources include an emergency response team that specializes in search and rescue, multiple police dog units, helicopters, drones and trained search and rescue volunteers.

Dickson saidthere's no evidence of foulplay. He said Brian Lush waswas supposed to be in North Sydney, N.S.,to catch the ferry home on Friday night.

Brian Lush is described as 5'10" with a medium build, 200 lb., brown eyes and short brown hair.He was last seen wearing a blue hoodie, jeans and possibly a ball cap.

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