The Island County animal control officer is asking the public for help solving an animal-cruelty case.

A pitbull suffered “massive trauma” and had to be euthanized after someone threw the dog out of a moving car Monday, Animal Control Officer Carol Barnes said.

The incident occurred at about 8 p.m. on Highway 20 near the intersection with Banta Road. A witness reported that a white-colored, four-door SUV slowed and a rear passenger opened the door and threw the dog out of the vehicle.

The SUV swerved and struck the dog. A vehicle following behind also struck the dog.

Good Samaritans at the scene jumped into action and transported the badly injured dog to the Pet Emergency Center in Mount Vernon.

Barnes said the dog was brought to Whidbey Animals’ Improvement Foundation in Island County, where she received a second opinion on the dog’s prospects of survival. But again, a vet found that the injuries were catastrophic. The dog was humanely euthanized Tuesday.

Barnes described the pitbull as a 6-year-old, red-colored female with white on her chest.

Barnes said the dog was microchipped, so she was able to track down the original owner. That person had given the dog, named Daisy, to a family member, but that person lost Daisy in June of 2016. Investigators don’t know who had been caring for the dog in recent months.

Anyone with information about the owner of the dog or the identity of the driver or occupants of the vehicle is asked to contact Barnes via the ICOM dispatch center at 360-679-9567 or Tips@co.island.wa.us.