Spirits were down at the Orange (CA) Police Department on Thursday as officers mourned the loss of one of their top K-9s, Bosco, who was euthanized late Wednesday after it was discovered he had a serious medical condition, police said.

Bosco, a 9-year-old German Shepherd, joined the OPD in August 2013. In less than 5 years of service, Bosco participated in more than 500 searches and racked up more than 60 arrests, including a number of dramatic pursuit finales. He also assisted in recovering large amounts of illegal narcotics and currency, Orange police Sgt. Phil McMullin told the OC Register .

Late Wednesday night, Bosco was demonstrating flu-like symptoms and was taken to the vet. Within hours, he was taken to an emergency room in Yorba Linda and it was discovered he had a severe medical condition. The situation was assessed and a tough call was made to have him euthanized, McMullin said.