Authorities in the US have shot and killed a critically endangered tiger after it bit the arm of a man who entered an unauthorized area of the tiger’s enclosure in a Florida zoo.

The man, who is in his 20s and worked for an external cleaning service at the Naples zoo in Florida, suffered serious injuries after an eight-year-old Malayan tiger named Eko bit him, authorities said on Wednesday.

“Preliminary information indicates that the man was either petting or feeding the animal, both of which are unauthorized and dangerous activities,” the Collier County sheriff’s office said in a Facebook post.

“Initial reports indicate that the tiger grabbed the man’s arm and pulled it into the enclosure after the man traversed an initial fence barrier and put his arm through the fencing of the tiger enclosure,” the statement said.

The first deputy kicked the enclosure and attempted to get the tiger to release the man’s arm from its mouth. The deputy was eventually “forced to shoot the animal”.

The man was then taken to a hospital by Collier county emergency medical services, the sheriff’s office said.