Detectives are unsure whether the teenage, who is from Sutton, was driving the vehicle when it crashed yesterday (Tuesday) and are appealing for witnesses to come forward.

Emergency services were called to the scene on Reginald Road, Sutton, shortly before 3pm and discovered the boy suffering from horrific injuries.

He had been thrown from the van. He was rushed to Whiston Hospital but has since been transferred to Alder Hey, where his condition is described as 'critical'. The lad's parents are at his bedside.

No one was else was found at the scene - but police are refusing to rule out the possibility another person was in vehicle and fled before the emergency services arrived, and want to speak to anyone who may have seen the van being driven around the Sutton area shortly before the crash.

Officers are still carrying out checks on the vehicle - a blue flat-bed Ford transit van - but suspect it was stolen from Cheshire in February and was being driven on fake registration plates (NU53 ZPN).

House-to-house inquiries have taken place in the area and officers are carrying out examinations at the scene in a bid to establish the cause of the crash.

* Anyone with information should contact Merseyside Police on 0151 777 5771.