Two people were arrested in Japan after a person broke into the viral macaque Punch’s enclosure, according to the zoo.

Ichikawa City Zoo, outside of Tokyo, said on social media Sunday that there was an “intruder” in the monkey enclosure. The pair were apprehended by police.

The zoo said it performed safety checks on the animals. It said that “no abnormalities” were observed, but that “countermeasures” would be put in place.

Starting Tuesday, the zoo said it would expand the viewing restriction area, install “intrusion prevention nets” and maintain constant patrols.

Images and videos online showed a person wearing a bright blue suit and a smiley-face mask scaling the fence and jumping into the Japanese zoo.

NBC News has reached out to local police for more information on those arrested.

Punch and his stuffed monkey toy won over the internet’s heart earlier this year after he was cast away by other monkeys living with him and rejected by his mother.