ARUNDEL — The Maine Warden Service and Maine State Police plan to expand their search Friday for a 65-year-old woman with dementia who they believed walked away from her home after the death of her husband.

The search follows the discovery of the body of Matthew Coito, 63, Wednesday afternoon in the kitchen of the couple’s house in Arundel.

A relative had gone to the home at 45 Campground Road to check on the couple after no one had heard from them since last Friday or Saturday, state police said. Matthew Coito’s wife, Sue Kim Coito, who has severe Alzheimer’s, was missing. Police believe she walked into the woods that surround their home.

A team of five tracking dogs and several game wardens and state police handlers searched a half-square-mile area south-southwest of the home Thursday as state police investigators tried to retrace the couple’s last steps and interviewed neighbors in the sparsely populated neighborhood where the Coitos lived.

On Friday, more dogs and personnel, including outside help from other agencies, are expected to converge on the area again to continue the effort.

“The key factor in this investigation is finding her,” said state police spokesman Stephen McCausland, noting that a well-known walking trail was the focal point of the search Thursday.

The Eastern Trail runs near the Coitos’ home, but it was not clear whether that was the area the search teams focused on Thursday.

Although the state Medical Examiner’s Office has completed an autopsy on Matthew Coito, the cause of death is being withheld pending the ongoing investigation. The time of Matthew Coito’s death has not been revealed. Mail in their mailbox did not appear to have been picked up in several days, and police are asking the public to report any possible sightings of Sue Kim Coito in the past five days. Their dog was found inside the home.

Matthew Coito’s death so far is not being investigated as a homicide and police do not believe there is a threat to the public, Sgt. Chris Harriman said during a brief news conference. There was no evidence of a break-in, and both of the Coitos’ vehicles are accounted for.

“We’re investigating it as a suspicious death at this point,” he said.

The Coitos bought their tidy, ranch-style home in 2005 from Sue Kim Coito’s sister, Kimberly Eaton of Biddeford.

In a brief phone interview, Eaton said the Coitos were both in their second marriage. She said her sister has one daughter from a previous marriage and Matthew Coito has two children from his previous marriage.

Eaton then said that both she and her sister are very private, and declined to comment further.

A neighbor who declined to give her name said she used to occasionally see the couple walk their dog along the road, but she had not seen them since the beginning of winter.

The neighbor said she worked briefly with Sue Kim Coito at a Biddeford manufacturing facility, but didn’t get to know her well, and she did not say much.

Sue Kim Coito is 5 feet 2 inches tall, weighs 130 pounds and has black hair and brown eyes. Anyone with information about her is being asked to call state police at 657-3030.

Matt Byrne can be contacted at 791-6303 or at:

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