A dog rescue organization's operator, who is accused of strangling a dog to death at a Toronto animal shelter this summer, has surrendered to police.

Rita Mueller, 50, of Bolton, Ont., turned herself in to Toronto police on Friday morning.

Rita Mueller, 50, operated Scooby's Dog House and Rescue, but police say it may no longer be in operation. (Toronto Police Service)

She has been charged with:

• Killing or injuring an animal other than cattle.
• Causing or permitting pain or injury or suffering to an animal or bird.
• Disobeying a court order.

Police said the dog, a Shar-Pei, had been removed from her care. The woman was supposed to be handing over the dog to a new owner when she came to a Toronto Animal Services shelter in August. She was then given a leash and muzzle to get the pet ready, police said.

But police allege she instead hanged the animal with the leash while inside the shelter's quarantine room, where the dog was being held after it allegedly had bitten someone.

Investigators say she had already fled the scene by the time shelter staff came in and found the dog without vital signs.

An autopsy determined the cause of death was choking.

Police said Mueller runs Scooby's Dog House and Rescue — an organization police say may no longer be in operation — and investigators say they fear she may own other animals whose safety could be at risk.

With files from The Canadian Press