Ontario Provincial Police confirm human remains found near Calabogie, Ont., belonged to Fouad Nayel, 28, an Ottawa man who had been missing since June, and a homicide investigation has been launched.

The remains were found Sunday in a wooded area near the intersection of Calabogie and Norton roads, about 100 kilometres west of Ottawa.

An autopsy conducted Wednesday confirmed the remains belonged to Nayel and confirmed the cause of death, which is not being released.

Police also found his black 2002 four-door Nissan Altima abandoned in Ottawa months ago, CBC News has learned.

The construction worker was last seen June 17 after he didn't show up for work and hadn't contacted his family or friends. Nayel's mother, Nicole, said at the time that it was out of character for Nayel to disappear.

Also in June, police said they believed the man was in the Calabogie area after they determined his cellphone was used there.

The homicide investigation is now underway with OPP and Ottawa police working together. Ottawa police said the investigation was first deemed a homicide probe in September, but that OPP have since taken the lead.

Headed to Petawawa, victim told friend

Nayel was in the Petawawa area when he was last seen. Nayel's friend, Adam Mounzer, told CBC News in June Nayel was heading there to see a friend and he was in "good spirits."

Officers from the OPP emergency response team combed the area in the Greater Madawaska Township for two days after the remains were found. Police also investigated the waters of Calabogie Lake for more evidence, CBC News has learned.

A passerby found the remains on public land while using it for recreational purposes, police said, near the shore of Calabogie Lake.

OPP and Ottawa police officers are working on the file. Divers and one airplane were also dispatched.

"It's a vast area it's very rugged terrain, and it is a challenge from a forensic and investigative point of view," said OPP Det.-Insp. Kevin Corcoran. "It's a very difficult area to conduct ground searches on, water searches on. But we're progressing, slowly and surely."

Anyone with information about this investigation is asked to contact the Renfrew OPP crime unit at 613-432-3211, or Ontario Provincial Police at 1-888-310-1122. You can also call Crime Stoppers at 1-800-222-8477.