A giant sea lion found impaled by a homemade spear last week has died after being rescued and sent to SeaWorld San Diego for treatment.

The marine park tells the San Diego Union-Tribune that the sea lion nicknamed Bubba refused to eat fish when offered and became increasingly lethargic.

SeaWorld spokeswoman Jennicca Taylor says he went into cardiac arrest during an exam Wednesday and died. Taylor says a necropsy indicates a chronic infection, inflammation and low glucose.

When found, veterinarians discovered the blade was so deeply embedded that it had to be cut out with a scalpel. Officials say it appears Bubba, who was estimated to weigh more than 600 pounds, was intentionally stabbed.

The metal spear was taken as evidence. Harming a sea lion is a federal offense.