Perth Zoo was placed in lockdown earlier today when two orangutans escaped from their enclosure, alarming onlookers.

A five-year-old male fell over a barrier and into a garden bed, sparking the incident.

A spokeswoman for the zoo said his mother dropped into the area to retrieve him before moving onto the visitor boardwalk and back into her exhibit voluntarily.

The zoo said visitors were removed from surrounding areas as per standard procedure.

It said the incident was over in about 15 minutes.

Both apes are now in their night quarters and have been checked by zoo vets.

The zoo spokeswoman said both animals are calm and in good health.

This was the second escape from the orangutan enclosure in two years.

A full investigation is underway.

– ABC