An investigation has found that a chimpanzee at the Honolulu Zoo escaped from the outer edge of the chimpanzee exhibit, which had a damaged wall, the zoo said in a news release on Wednesday.

The zoo is expediting repairs to the wall and modifications to the exhibit and hopes to reopen the exhibit in about a month.

Pu’iwa, a 14-year-old chimpanzee, escaped from the exhibit at the Honolulu Zoo on June 25 and was free for about an hour until he was subdued with a tranquilizer dart and returned to the exhibit.

A visitor saw the chimpanzee outside of the exhibit at about 4 p.m. on June 25. People in the zoo were ushered to a protected area until the chimpanzee was returned.

Pu’iwa is said to be recovering well, with his troop and all eight of the zoo’s chimpanzees living in their sleeping quarters until the repairs are made, the news release said.

Zoo officials closed the chimpanzee exhibit while they investigated the escape.