Mary Beth Singh was making the same drive from her home in St. Petersburg to her office in Tampa she has made for 12 years when she glanced out the window and saw something that made her sick to her stomach.

A white and silvery gray tabby cat was lying motionless on the left-hand side of the Howard Frankland Bridge northbound near mile marker 35, approaching the hump.

At least five dead cats have been seen along the Howard Frankland over the last 15 days. All five have been found on the left side of the road approaching the hump, but it's unclear how they got there.

In the month Chris Slattery has lived in St. Petersburg, he has seen three dead cats on his commute. They're always on his way to Tampa, always on the left side of the bridge and always dead.

"It definitely seems too far for them to be getting there on their own," Slattery said of the spot, about 3 miles from the nearest land. "And it's always on the left side of the road. … The right side has enough room for a car to pull over, but they're always on the left."

A few days after she saw the first cat, Singh was on her way to work once again and noticed another one. This time, the cat was alive, but badly hurt. It was different from the last one — this one was tortoise-shell colored and curled up in a ball against the wall.

Singh said the cat lifted its head up and looked right at her, so she called the Florida Highway Patrol.

The next day, she made the drive again, praying that she wouldn't pass the injured cat.

"I kept thinking, 'Please let that cat be gone, please let that cat be gone,' " she said. "And it was gone. But then there was another one."

This time, the cat was black and white and definitely dead. It was the third cat she'd seen in less than two weeks.

The Florida Highway Patrol has received one report of a cat on the left shoulder of the bridge at the 35 mile marker, Sgt. Steve Gaskins said. But the trooper was unable to find any cats.

Bill Cowherd has seen two cats on his way from Pass-a-Grille to Tampa, where he owns a warehouse. Usually, he's got his eyes fixated on the cars ahead of him, but the dark tabby he saw at the end of May caught his eye.

"I don't know why it'd cross a bridge because cats aren't too keen on water," he said. "Why would the cat walk over the bridge? I felt sorry for it. What a way to go."

Georgina Race works with both Urgent Cats of Tampa and Save Our Strays, so when she saw a small orange cat on the side of the road, she was perturbed.

"I thought, 'How on earth does a cat get out here without someone's help?' " she said. "I felt horrible because I know someone must have dumped it. . . . I feel like people do it on purpose, honestly. People are sick."