VANCOUVER -- Update, Saturday April 25, 2020: RCMP announced the search has been concluded and the missing person's body has been found. Foul play is not suspected.

Mounties in Chilliwack say the "unfolding police incident" they warned the public about early Thursday afternoon is now a missing person investigation.

Police are still warning members of the public to call 911 if they see a grey Toyota Tacoma pickup truck with licence plate PA558R.

That truck belongs to 39-year-old David McCullum, who last contacted his family Thursday morning and has not been heard from since, according to Chilliwack RCMP.

McCullum's last known location was at the south end of Columbia Valley at around 9:30 a.m., police said, adding that they have been unable to find either him or his truck "despite extensive aerial and ground searches of the area."

Anyone who sees McCullum or his truck is asked not to approach him. Police say he "is believed to be in possession of firearms."

Police describe McCullum as white with brown hair and brown eyes. He stands 5'10" and weighs 161 pounds, and he was wearing a dark grey hoodie at the time he was last seen, police said.

“Police, family and friends are very concerned for David’s wellbeing,” said Sgt. Krista Vrolyk, spokesperson for the RCMP's Upper Fraser Valley Regional District, in a news release. “While we continue to ask the public to be vigilant, our primary concern is to locate David and get him the help he needs.”