Parts of Perth Zoo went into lockdown on Sunday after a female orangutan and her baby escaped their enclosure.
The mother reportedly went to rescue her offspring after he fell from some equipment.
"Keepers are quite panicked, asking people to keep calm then to move quicker as it's an emergency situation," witness Jess McConnell said.
"The mum leapt down from the silver tower onto the banana tree and the zip line which reverberated the walkway.
"She then got up on the walkway railing before moving along and grabbing her baby then moving back on the railing."
They'd got out of an enclosure that was designed so to be impossible for them to escape.
Incredibly, it's not the first time it has happened either. Another orangutan got out of a different enclosure two years ago and managed to walk among some startled visitors.
A Perth Zoo spokesperson confirmed the younger orangutan, Sungai, lost his grip and fell out of the enclosure while playing, so his mother Sekara jumped out to save him.
"His mother, Sekara, who is known for her excellent maternal instincts, then dropped down to retrieve him, moving onto the visitor boardwalk, before moving back into her exhibit voluntarily," a Perth Zoo spokesperson said.
The area reportedly reopened after 20 minutes after the animals were returned to their enclosure.
The zoo has launched a full investigation.
The incident happened on the first anniversary of the death of Harambe, a gorilla shot dead by Cincinatti Zoo staff after a child fell into his enclosure.
7 News / Newshub.