Five lions broke out of their enclosure at Sydney’s Taronga zoo on Wednesday morning, forcing staff to hide in “safe zones”.
The lions – four adults and one cub – were seen outside their enclosure at about 6.30am.
A code one, the zoo’s “most active code”, was called shortly after 7.30am, sending the zoo into lockdown, with reports a siren could be heard in neighbouring areas.
Zoo spokesman Simon Duffy told reporters the lions were seen in a “small area adjacent to the main lion exhibit”.
“A six-foot fence separated them from the rest of the zoo,” he said. “The zoo has very strict safety protocols in place for such an incident and immediate action was taken.”
Duffy said the cub needed to be tranquillised, but otherwise the lions “calmly made their way back” to their enclosure.
“All animals are now safe in their back of house exhibit and are being closely monitored.
“I would remind everyone that Taronga zoo itself has its own safety perimeter fence.
“So at no time did the lions exit that area or exit Taronga zoo.”
Duffy confirmed a review of the incident was underway, with the exhibit to undergo further inspection to ensure it is “100% safe”.
Police were called to the zoo, saying they were there as a precaution only, with no injuries reported.
The zoo confirmed the area was safely secured shortly before 9am.
“An emergency situation occurred this morning at Taronga Zoo Sydney when five lions were located outside their enclosure,” the zoo said in a statement.
Aerial footage showed keepers patrolling the ground during the emergency.
“All persons on site were moved to safe zones and there are no injuries to guests or staff.
“All animals are now in their exhibit, where they are being closely monitored.”
The zoo, on Sydney’s lower north shore, confirmed it would be open on Wednesday.
“The zoo will be open as normal today. Further details will be provided when possible.”
School visits and tours were not expected to be affected by the incident.
The incident comes nearly three years after a group of baboons escaped a research facility near Sydney’s Royal Prince Alfred hospital.
Animal escapes are rare at Taronga, but keepers are reportedly ready for such events with a plan of action involving anaesthetic dart guns and nets.
In 2011 former Taronga keeper Terry Boylan told Australian Geographic most animals were “very reluctant” to leave the security of their enclosures.
In 1946 a Bengal tiger escaped into zoo grounds. The visiting public were herded into an empty seal enclosure while the animal was hunted down by staff.
In 1972 a young female orangutan managed to climb on to the roof of the ape house after ripping up her cage’s floorboards.
In the mid-1950s former circus chimp Koko escaped and sprinted through the deserted zoo before leaping into the office manager’s car, where she was chloroformed by keepers.
A Himalayan mountain goat once bounded over its three-metre stone wall and made it as far as some Balmoral parkland.
And in 1967 an entellus langur monkey escaped its concrete pit and made it as far as nearby Bradley’s Park, where it was shot by a zoo director.
In 2009 a lion escaped its enclosure at Mogo zoo on the south coast.