FREMONT (KRON) — A Fremont police dog died Monday after suffering a heart attack, police said Friday.

K9 Kalimero had a heart attack after undergoing emergency surgery for intestinal torsion, which is a twisting or blockage of the intestines, according to police.

Kalimero was found Monday in Officer Tyler Layfield’s backyard with the intestinal torsion and was rushed in for surgery. He appeared to be doing well after the surgery but died later in the day, police said.

He was four years old and had been in the department for two years before he died, according to police.

“Kalimero will remain in our thoughts and be missed by us all,” police said in a statement.