Cruel prank leaves a 9-year-old Australian boy "nearly strangled" at a local park.

A nine-year-old boy from South Australia has suffered neck injuries after being coat-hangered by a rope while riding his bike.

Stuart Heath was riding at Port Lincoln’s Centenary Oval and was “nearly strangled” after three kids told him to “ride faster”, his mother claimed in a Facebook post.

Stuart's rope burn. Image via Facebook.

Katherine Price told Seven News she believed the rope was deliberately hung by a group of children playing a cruel prank.

"I think the kids might've done it just for a bit of fun and didn't realise what harm it could've really had," she said.

The rope was said to be hung between a flagpole and a fence.

 "He thought he was going to die," Ms Price told Nine News.

"He couldn't breathe at the time.

"The rope could have really got caught and it could have led to something a lot worse," she added.

The boy, who was taken to hospital on the weekend, has rope burn marks around his neck.

The incident has not yet been reported to the police.

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