OKEECHOBEE, Fla. — UPDATE: According to the police chief, the officer involved in the shooting has been cleared and is now back on duty. He was on administrative leave which is standard protocol.

EARLIER:

The Okeechobee Police Department said a police officer was forced to shoot and kill a man's service dog late Monday night after the animal was aggressive, grabbing the officer's arm and tearing his pants.

However, the owner of the dog, Larry Massey, said the officer misunderstood what was happening because Massey was having a seizure.

According to a news release from the city, police received a call at 11:59 p.m. by a passerby who said a man was passed out on the side of the road in the 700 block of S. Parrott Ave. in Okeechobee.

Two officers, identified by the city only as Rojas and Daigneault (their first names were not provided), arrived at that location and found Massey unresponsive.

Police said Massey had informed officers in the past that due to a medical issue, he has seizures. The news release said Rojas did a "sternum rub" to revive Massey.

While Rojas was assisting Massey, police said Massey’s dog, Butch, growled and attacked Daigneault, grabbing his right pant leg with his teeth and tearing his pants.

Police said Daigneault pushed the dog away with his foot, but the dog lunged at Daigneault again, grabbing the officer’s arm.

Daigneault pushed the dog away a second time, but the dog lunged at Daigneault's face. Police said Daigneault then shot the dog once to protect himself and others.

"This is an unfortunate situation because the officer was doing what he's trained to do, protecting himself and other people," said Okeechobee Police Chief Robert Peterson in an exclusive interview with WPTV on Tuesday.

🔽 WATCH INTERVIEW WITH CHIEF 🔽

WATCH: Okeechobee police chief talks about service dog shooting

The dog was transported to a local veterinarian’s office, North Lake, but was pronounced dead upon arrival.

Chief Peterson told WPTV the officer fired because he was protecting himself, and said he had no other options. The chief added Daigneault is doing OK but is upset.

"You really feel for the dog, and the dog's owner, and the officer," said Chief Peterson.

Daigneault is on administrative leave, which is standard in cases when an officer fires a weapon.

Police said the dog was not wearing a service dog vest, but did have a badge that Massey obtained online. Chief Peterson added that investigators don't believe the animal was a formally trained, certified service dog.

"It was a service dog to that individual," said Chief Peterson. "He does have seizures, and he felt the dog was helpful to him and provided him support. So as far as we're concerned, for him it was a service dog."

Chief Peterson said his agency has had interactions with Massey in the past and knew he had seizures. However, they don't know why the dog acted the way it did.

"We have independent witnesses that actually saw the dog attack the officer, and the officer didn't shoot the dog until it made its third attempt at biting him," said Chief Peterson. "So unless something else comes up in the investigation, where we stand now, the officer acted appropriately."

The case is under investigation.