Durham Regional Police have released a video of a person of interest in connection with a violent assault in Whitby that left a woman in critical condition.

In the video, a person of interest can be seen walking westbound on Taunton Road near Anderson Street between 8:50 p.m. and 9 p.m., on July 28. Police said the unknown man was following the 50-year-old female victim, keeping pace about 150 feet (45 metres) behind her.

The person of interest is described as having a medium build, wearing a white t-shirt with dark sleeves, loose-fitting shorts with a dark horizontal stripe down the side, dark socks and dark shoes.

The next morning at 10:25 a.m., the victim was found with multiple, serious injuries consistent with an assault near a creek southeast of Taunton and Anderson, police said.

Investigators said she was brought to the Oshawa airport and was flown by air ambulance to a Toronto trauma centre for treatment.

Officers identified the victim as someone who was reported missing late the night before after going for a walk in the area.

Police said they searched for her overnight and into the morning using a police helicopter and a K-9 team until she was located.

The victim remains in hospital with life-threatening injuries.

“The family has asked the media to respect their privacy during this difficult time," Whitby mayor Don Mitchell told CTV News Toronto. "What I can say is that we all hope to see the perpetrator identified soon. Until then, I would urge residents to exercise caution and stay safe.”

Police said the victim and the person of interest are not known to each other.

Officers confirmed to CP24 that members of the homicide unit have taken over the investigation due to the "unusual" nature of the case.

Investigators would like to talk to any drivers who were in the area during the time of the video who may have other dash-cam video that recorded the person of interest.

A command post has been set up at 4240 Anderson Street, just north of Taunton Road. Police are urging any witnesses to visit this location to talk to investigators.

Anyone with information can also contact Crime Stoppers anonymously.