Authorities Investigating Video Showing Dog Chained to Trailer Driving 70 mph on Florida Highway

— -- Authorities in Florida have launched an investigation after a video emerged on Facebook of a dog chained to the top of a crate being towed by an SUV driving at least 70 mph.

Palm Coast resident Brenna Cronin, 24, shot the video Wednesday afternoon in Flagler County as she and her boyfriend were driving southbound on I-95 toward Daytona Beach. In the video, a dog is seen standing on top of the crate, which contained at least one other animal, while a Chevrolet Tahoe pulls the trailer at high speeds.

Cronin said she and her boyfriend were shocked to see the dog traveling in that manner, so she pulled out her video and began to film it.

"I was just completely outraged and appalled," she told ABC News Thursday. "I couldn't believe it."

Once the driver realized Cronin was filming him, he "gave me the finger," she said. Cronin said she is "happy" that the video she took led to an investigation of the owner.

"The dog stood up and was looking at me so sad," she said. "I had to do something."

As of Thursday afternoon, the Facebook video has been viewed more than 500,000 times, with hundreds of people expressing outrage over the dog's condition in comments.

The owner, who did not wish to be identified, told ABC Jacksonville affiliate WTLV that it was an "OK" way to transport dogs and that it is "how everybody transports."

Flagler Animal Services is investigating the video, said Jeffery Ritter, development coordinator for the Flagler Humane Society. The dog seen in the video is a Blue American Pitbull Terrier named Zeus, who does not like to ride in the crate, Ritter said. So his owner, who said he uses the dog for hunting, allows him to ride outside, Ritter said.

A Flagler County ordinance allows people to travel with a dog in that manner as long as the animal is tethered twice to the vehicle. Dogs being transported in the open bed of pickup trucks or any other type of open vehicle must either be confined to a pen or be restrained by a "minimum of two tethers or some other similar method to safely control or restrain the dogs from easily escaping the vehicles," No. 93-15 S 4, 11-15-93 of the Flagler County Code of Ordinances states.

Zeus was only tethered to the trailer once, Ritter said.

"The driver didn't have any bad intentions," he said. "...He honestly didn't know any better."

Zeus' owner is cooperating with the investigation and has agreed to allow animal services to conduct wellness checks, Ritter said.

Once the Humane Society wraps up the investigation, it will turn over its findings to the Flagler County Sheriff's Office, which will determine if a crime was committed, Flagler Police Chief Mark Strobridge told ABC News. At minimum, Zeus' owner faces a ticket and fine under the Flagler County Ordinance, Ritter said.

Although it is legal in Flagler County to travel with a dog in an open vehicle, Ritter said the Humane Society "would not recommend it at all" and stressed the "importance of having any pet secured when driving."

"Don't let your dog sit in your lap when driving," he warned pet owners. "Make sure your animal is contained while you travel. It's dangerous for them as well as you and other drivers."