LYNNWOOD — The kitten was too weak to move, but it had just enough energy to cry.

Someone had stuffed the black-and-white kitten into a blue Mariners duffel bag filled with clothes. The bag had been left on the ground next to a trash bin outside an apartment complex in the 15900 block of Highway 99.

It’s unknown how long the cat baked in the afternoon sun Wednesday before a man who lives in the apartment complex heard its cries.

The 6-month-old cat was brought to the Progressive Animal Welfare Society in Lynn­wood, where staff members wrapped it in cool blankets and gave it intravenous fluids. By Thursday, the kitten, named Sunny by the society’s staff, had made a full recovery.

“We’ve had other cases where people have found animals abandoned inside apartment buildings, inside vehicles, things like that,” said Kay Joubert, the society’s director of companion animal services. “But it’s rare that someone has gone to the level of stuffing them in a bag and leaving them (by) a dumpster.”

Snohomish County Animal Control is investigating the incident. Anyone who has information about what happened to Sunny can call the animal control services hotline at 425-388-3440, ext. 9.

“We don’t hear of this very frequently,” Snohomish County License and Animal Control Services Manager Vicki Lubrin said.

Sunny was suffering from heat stroke when he was brought to the animal rescue. His body temperature was 107 degrees. A cat’s normal temperature ranges from 100.5 to 102.5 degrees. Sunny was panting, collapsed and unresponsive.

Now, the frisky kitten appears well enough to be available for adoption Tuesday, Joubert said.

“He’s fabulous. He gets right into your arms and purrs,” Joubert said. “He’s really interactive in his cage, and he has lots of spunk and energy. I think he’d make someone an excellent companion, and it’s just so sad this happened to him.”

PAWS can be contacted at 425-787-2500.

Reporter Scott Pesznecker: 425-339-3436 or spesznecker@heraldnet.com.