POLICE ARE investigating a crash involving two motorbikes at Crystalbrook near Proserpine on Saturday night.

Emergency services were called to Spoor Rd about 7pm after reports two teenagers were seriously injured when the dirt bikes they were riding collided.

An 18-year-old man sustained severe head injuries and was flown to Townsville Hospital in a critical condition.

A representative for Queensland Health said the man remained in a critical condition in hospital yesterday.

The second youth involved in the crash was 15-year-old Anthony Pendlebury, a young BMX rider from Proserpine.

Anthony received multiple fractures and was flown to Mackay Base Hospital.

Yesterday he was in a serious but stable condition.

His mother, Mary, posted on Facebook she was grateful for the response of the RACQ CQ rescue helicopter and applauded Proserpine Hospital staff.

"I'd like to say a big thank you to the staff and ambulance officers at Proserpine Hospital and the RACQ helicopter staff for the quick response care of my son Anthony Pendlebury and the other young man involved in the motorbike accident Saturday night,” she wrote.

"(As well as) the ongoing support from family, friends and our BMX family.

"My heart goes out to the other young man and his family, wishing him speedy recovery.

"Anthony is in good hands at Mackay base and is stable and is on what will be a slow road to recovery.”

The Forensic Crash Unit is investigating.

In another incident, emergency crews were called to a single-vehicle rollover on the Bruce Hwy early on Monday in which three people were injured.

See page 3 for details.