Driver flees crash in northern Sydney

A driver has fled the scene of a late-night crash in Sydney's north which left a 25-year-old passenger seriously injured.

Police say they are yet to determine if a man found lost in bushland hours later is linked to the incident.

Emergency services were called to Leighton Place in Hornsby about 11.30pm on Friday after a Nissan Skyline crashed with a parked Toyota Hilux and the driver fled.

They found and freed the trapped 25-year-old male passenger, who was taken to hospital in a serious but stable condition.

A second 23-year-old male passenger wasn't injured.

Police are asking any witnesses to come forward as they try to identify and find the driver.

They don't yet know if the rescue of a lost 22-year-old man in Hornsby bushland, about 3am on Saturday, is linked to the crash.

The 22-year-old was taken to hospital in a stable condition.