POST FALLS - Police are searching for missing Coeur d'Alene 70-year-old Joan Gundlach, who reportedly had been suicidal.

Police suspended an active search for her on Wednesday morning in the Q'emiln Park trail system and the Spokane River after about 10 hours of looking.

"This remains an active investigation and our priority is to find Joan," said Post Falls Police Capt. Pat Knight. "It's a missing person case with suspicious circumstances.

"We treat all such cases as a homicide until we can prove it differently."

However, there are no suspects or persons of interest, Knight said.

A Post Falls officer discovered an unoccupied, parked vehicle at the park's trailhead just after midnight Wednesday. The officer contacted Gundlach's husband and learned the woman had been possibly suicidal when she left home on Tuesday at 10 a.m. She has not been seen since.

Knight said the husband acted "odd" when contacted by police.

"We didn't get the response that we would typically get when a spouse goes missing," he said.

Knight said Gundlach's 76-year-old husband went to the park and found the car based on a suicide note left on the bed, but didn't report her missing to police. He told police the reason he never reported the case was because he was distraught over her being missing.

Knight said another suicide note was left in the vehicle. He said investigators assume the notes were left by Gundlach, but police are still gathering facts.

"We are still too early in the case to rule out anything," PFPD Capt. Greg McLean said.

Gundlach's husband told police the couple have been married 30 years. He said his wife has been depressed off and on for several years, but never sought medical help.

Knight said that, based on reviewing park surveillance, they believe Gundlach entered the park and didn't come out. No evidence outside the vehicle at the park or along the river were located. Knight described the vehicle, which was impounded by Post Falls Police, as being tidy.

A clothing description for Gundlach was unavailable. Joan is a white female, about 5-foot-8, 155 pounds with brown hair and brown eyes.

PFPD was assisted by the Kootenai County Sheriff's Office and a MedStar helicopter in the search of the park and river. Knight said the helicopter made multiple trips up and down the river from the Post Falls Dam to Spokane.

Knight said it's being explored whether the water flow at the Third Channel of Post Falls Dam, near where the vehicle was located, can be altered to perform a more extensive search of the river in that area.

"We have no evidence she's even in the river," Knight said, adding that's just one of several sites where she could be.

Anyone with information is asked to call PFPD at 773-3517 or leave an anonymous tip at www.postfallspolice.com.