An Australia Day horse race had to be abandoned thanks to some gatecrashing kangaroos.

The obstinate roos bounded over a fence designed to keep them out after they invaded last year’s event at Hanging Rock in Victoria, Australia.

Last year several of the iconic Australian marsupials were skittled by the course ambulance.

This time round a small group of the hundreds of kangaroos that inhabit the area, were particularly determined to run riot.

 “We’ve put fences up but they came off a Usain Bolt run-up and jumped over,” said racing club spokesman Mark Graham.

“We tried to gently usher them out but they just kept coming back. They’re so friendly with humans that they wanted to mingle.”

Chief steward Peter Ryan declared the invasion an unacceptable safety issue and the meeting was abandoned before a race had been run.

The decision prompted a groan from only a few of the estimated 6000 revellers.

“It’s a damned shame, but it’s just one of those things.” Ryan said.

“The kangaroos posed too much risk to horses and riders.”

Graham said most revellers accepted the invasion with good humour.

“Most of them have hung around, sitting on the lawns having a beer and a chat,” he said an hour after the cancellation. “I’m not sure half of them are aware we’ve even called it off.”

The first race was delayed three times – twice when the horses were in their starting stalls – when kangaroos were spotted entering the track from the northern boundary.

Mick Sell, trainer of Oskaiben Prince who was to run in the 1800m maiden, said it was “a kick in the bum” for everyone, but couldn’t be helped.

“You’ve got to look after the jockeys. It’s no use one of them getting killed due to a kangaroo,” he said.

The kangaroos sure know how to rain on someone’s parade.

The race was to be the final one for veteran race caller Jack Styring.

He was to call the Hanging Rock Cup for the 39th and final time as a favour to the club, where he was once its longest-serving committeeman.

Styring, 82, will instead call his last race at the Yea picnic meeting on Saturday.

Mr Graham was unsure if the Hanging Rock meeting would be rescheduled.

The club’s only other meeting for the year was on New Year’s Day.