THE Environment Agency is investigating after thousands of tyres were dumped in Co Tyrone.
Up to 100 tonnes of tyres were left on land near Pomeroy.
Arrangements are being made to have them disposed of properly.
According to the BBC, the landowner claimed a relative had planned to build a go-kart track but more tyres arrived than expected.
He said he was unable to contact the relative and was not sure where they had come from.
Stricter controls in the key export market of India are believed to have increased the numbers of used tyres in circulation and the cost of properly disposing of them.
Dasos Michaelides from the National Tyre Distributors Association, an industry body which represents tyre retailers, said illegal dumping was a scourge carried out by "unscrupulous" people.
He said it has been happening regularly in recent years, including at tourist spots like the Giants Causeway.
He said tyre sellers and collectors had to comply with licence conditions to ensure waste tyres were dealt with correctly.
"There's been some well-publicised cases of tyre dumping and we all understand the limited resources, but enforcement needs to happen – end of story, it really does need to happen," he told the BBC.
"If someone unscrupulous turns up at your place offering to take your tyres away don't be fooled by a cheap price."
More than two million used tyres are produced by motorists in Northern Ireland every year.
Around half are treated at the north's only licensed recycling plant in Co Antrim, which turns them into products including soft surfaces for playgrounds.
