Two men die in late-night crashes in NSW

Two men have died in separate crashes in NSW, one in an allegedly stolen vehicle in the Blue Mountains and the other after hitting a tree in Sydney's west.

A taxi, which investigations suggest was stolen at knifepoint 20 minutes earlier in Lithgow, collided with a truck on Bells Line of Road at Bilpin around 10pm on Tuesday.

Police say the taxi's male driver, who has yet to be identified, died at the scene and Bells Line of Road was closed in both directions for several hours. The truck driver was uninjured.

In the second crash, a 20-year-old man died when his Mitsubishi Lancer left the road and struck a tree in Rhodes at 11.20pm.

Police say the driver died at the scene while his female passenger was taken to Westmead Hospital with minor injuries.