A baboon monkey who was to undergo sterilization in Australia yesterday escaped with his two wives, and the trio ran through the streets of the country's largest city to find safety.

Animal guards and police were called in after the trio escaped from a truck en route to Sydney Hospital during the evening rush hour.

One of those animals was preparing to undergo the operation, while the other two were there "to help him keep calm," state health minister Brad Hazard told local media.

He added to the newspaper, "The Daily Telegraph": "His wife came to stay by his side while undergoing sterilization."

Videos circulated on social media showed the three monkeys passing between cars, while passers-by were watching what was happening amazed.

A New South Wales police spokeswoman advised people to avoid the area, but said there was no immediate danger to the public. The runaway animals were eventually arrested.