TAMPA — Three cats sat on Pam Duval's desk every day.

So when she got the call early Saturday about a fire at the Animal Coalition of Tampa Bay, she hurried to the scene. Amid the billowing smoke, Duval told firefighters where they could find the cats. The feline trio roamed free at night in the clinic's administrative area.

Firefighters brought her Jazz, Boy and Mama wrapped in blankets. The smoke had been too much.

"I told them goodbye," said Duval, the organization's comptroller. Her hands and shirt were sooty as she fought back tears.

As news of the suspected arson spread among 46 employees at the low-cost spay, neuter and vaccination clinic near the University of Tampa, one question persisted: Who would do this?

"I'm just trying to figure out which end is up," Frank Hamilton, the nonprofit clinic's president said as he stood outside with more than a dozen employees. Inside the heavily damaged facility, a dog treat jar and an empty glass donation jar stood on the counter. When Hamilton arrived, he said, the jar had about $100 and so did the cash register.

The staff is dedicated and happy to work there, he said. The nonprofit's mission is to end euthanasia as a means of population control. Workers made calls at 6 a.m. to cancel 40 appointments Saturday for spaying and neutering. Pet owners pulled up to the clinic throughout the morning for a vaccination event offered with no appointments.

The clinic is closed until further notice, and Hamilton said to check their website at actampa.org for updates.

Firefighters arrived just before 5 a.m. at the clinic, 502 N Gilchrist Ave., and quickly doused the blaze.

Separate fires were started in multiple spots within the building, which is one of the ways investigators determine arson, Tampa Fire Rescue spokesman Jason Penny said.

A pit bull that had either been let out or escaped was found in the back yard, according to Tampa Fire Rescue. Its owner had dropped it off Friday evening, saying he didn't want it. Clinic workers had offered to keep it overnight and the owner returned Saturday morning to pick it up.

The state Fire Marshal is investigating the suspected arson. Anyone with information can call the Fire Marshal's Office at (813) 274-7000 or leave an anonymous tip at www.tampagov.net/arsontips. Rewards of up to $2,500 or more are available for information leading to the identification of a suspect or suspects.