The body of an 18-year-old man has been found in a north Queensland river.
The man was discovered in the Ross River at Townsville by police divers about 11.45am.
Police said they believed he was in travelling in one of two stolen cars targeted with a tyre-deflation device early Thursday morning.
Acting Superintendent Brad Inskip said the occupants of the vehicles had then fled and it was then believed the teenager and a 22-year-old man entered the water.
Acting Superintendent Inskip said the police dog squad was deployed as part of the search but did not arrive until about 40 minutes after the men had fled.
"They did conduct a track from one of the vehicles to the river but lost the track in that location."
He said the death was being treated as the result of a police operation and an investigation will be overseen by Police Ethical Standards.
"There's no indication that the police have chased anyone into the river, there's no indication the police have done anything wrong.
"Their actions prior in the incident will be part of the investigation and the overview."
Earlier today a land, air and river search involving water police, SES and the Townsville rescue helicopter began after a preliminary search last night failed to locate the 18-year-old.
The older man is safe and well.
Acting Superintendent Inskip said police had been unable to locate any other passengers travelling in the cars.
Earlier this week, police said two stolen cars were driven onto a football field during a practice, narrowly avoiding children and parents.