Jetstar passengers returning from Byron Bay music festival Splendour in the Grass on Sunday night were warned of sniffer dogs and police waiting for them at the airport.

An attendant on the evening flight to Sydney made a cabin announcement telling passengers to hide evidence of illicit drug use before landing.

“We have been told there are sniffer dogs and quarantine officers waiting in the domestic terminal,” he told passengers.

“If you need to dispose of anything you shouldn’t have we suggest you flush it now.”

Passengers were alarmed by the announcement, which prompted a sudden rush to the toilets.

“I was shocked,” one passenger told The Daily Telegraph.

“Why would you tip people off about this? If they have got something illegal, let them get caught. I obviously couldn’t tell if people were flushing things but several of the people who suddenly got up to queue for the toilet had things clenched in their hand.”

Jetstar have confirmed that the unusual announcement was indeed made, but it blamed it on a casual staff member who strayed from the usual script.

“We’re required to play a pre-recorded quarantine announcement for customers on all flights across interstate and territory borders within Australia,” a Jetstar spokesman said.