Donald James Barnett ((RCMP))

Police and search and rescue teams have come up empty in their search for an 86-year-old man who disappeared northwest of Regina on Thursday — and now they're asking the public for help.

They're asking for information and knocking on doors to ask people about Donald James Barnett, who was last seen at 9 a.m. CST when he drove out to the Wascana Trails for a walk and to take photos.

He was expected home in the afternoon and when he did not return, his wife reported him missing.

Barnett's locked car was found in a parking area of the trails, which are about 28 kilometres northwest of Regina.

RCMP members launched a search Thursday and were joined by search and rescue teams later that night. They worked through the night, using thermal imaging cameras to scan for any signs of the man.

They called out, but didn't get any response. In the morning a search plane scoured the area and an unmanned aerial vehicle was brought in to continue the work from the air.

"We're going to be looking for someone who is not responsive to us," said Hugh McLaughlan, who is co-ordinating the search. "And that means we need to tighten up our search a little bit."

Barnett is known as a regular hiker who's in good shape.

"I'm pretty confident that if he's here, we will find him," McLaughlan said.

About 15 people were involved in the search Friday morning, including a dog team and people in canoes, but the search at the trails was suspended early in the afternoon.

Police said they expect to return to the trails, but for now they'll go door to door to homes in the area to see if anybody saw anything. They'll also be searching nearby rural roads.

Police are asking member of the public who might have seen Barnett or his vehicle to contact the Regina RCMP at 306-780-5560 or Saskatchewan Crimestoppers at 1-800-222-8477.

The recreation area is in a long, shallow, winding valley, with steep sides dotted with thick brush.

It also includes a small river and a number of flat areas of tall grass meadow. Several hiking and mountain biking trails intertwine with each other.

People who might have seen Donald Barnett or his car are asked to contact the police. The locked car was found at the parking lot at the Wascana Trails northwest of Regina. (RCMP)