18/01/2016 2:00 PM AEDT | Updated 15/07/2016 12:51 PM AEST

Jaws-Sized Great White Shark Cruises By Surf Carnival With 1000+ Kids In The Water

Universal History Archive via Getty Images
'Jaws' a 1975 American Thriller film starring Roy Scheider. (Photo by: Universal History Archive/UIG via Getty images)

A great white shark about the size of Hollywood beast Jaws has been spotted near a kid's surf carnival in South Australia.

The shark was spotted by Surf Lifesavers on patrol in the Westpac Lifesaver Rescue Helicopter on Sunday about 200m offshore Marino Rocks, 18km south of Adelaide's CBD.

Lifesavers described it as "unusually large", estimated at 6-7m long.

To put that in perspective, the average man is 1.7m long, a Holden Commodore is 4.8m long and this shark was 6-7m long. And Jaws? He was 8m.

This just sent in of the massive 7m White spotted off Marino Rocks this afternoon from the Westpac Heli.

Posted by Shark Alerts South Australia on Saturday, January 16, 2016

Less than 1km away, a children's surf carnival was on at Seacliff Beach with more than 1000 people in the water.

It was cancelled and Surf Life Saving staff manned the beach via boat, jetski and helicopter but a spokeswoman said the shark swam out to deeper water quite quickly.

Right now at Marino Rocks and Sea Cliff where a suspected shark has been sighted, thanks to Edd Westbrook for the quick response.

Posted by Shark Alerts South Australia on Saturday, January 16, 2016

Sharks are by no means uncommon at Seacliff Beach but Westpac Lifesaver Rescue Helicopter data suggested numbers were increasing.

A spokeswoman said there were 53 confirmed shark sightings from the helicopter patrol for the 2015/2016 surf lifesaving season so far compared to 30 sightings recorded for the same period in 2014/2015 and 39 sightings in 2013/2014.

Surf Life Saving SA chief executive Clare Harris said the increase could be due to large schools of bait fish.

“While there is no evidence at this time that there is any greater risk than in previous years, Surf Life Saving SA in consultation with officers from SA Police and PIRSA Fishwatch, encourage everyone using the water to be aware that there are large schools of fish moving through our waters at this time of year and therefore the chance that a shark may be following these is possible," Harris said.

“If a member of the public does see a shark which poses a threat to human safety we recommend that they call 000 and the police will activate the closest emergency service asset to deal with it and alert the public."