A police dog was shot and killed after he suddenly attacked an officer Tuesday morning, according to Fresno police officials.

Last October, officials say K-9 Odin attacked and seriously injured an officer, who had to be hospitalized for his injuries.

After considering the safety of the public and officers, officials say the decision was made to remove K-9 Odin from service.

Over the course of several months, Odin’s behavior continued to decline and he started to become more aggressive toward those caring for him.

Following a final assessment, the department made the difficult decision to euthanize Odin.

On Tuesday morning, Odin was scheduled for the procedure and members of the K-9 unit gathered to take him to the veterinarian’s office.

Officials say Odin continued to be extremely aggressive despite being given prescribed sedatives. Odin ended up biting a K-9 officer on his arm.

The officer wasn’t able to get Odin to release his grip, so officials say he was forced to shoot him.

“Members of the Fresno Police Department are truly saddened with this incident, and we will be forever grateful for his years of service to our community,” Fresno police officials wrote in a press release.

K-9 Odin was 4 years old and had served with the Fresno Police Department for three years.