About 7pm on Saturday, emergency services were called to Mini Mini Forest Road at Ganbenang, near Lithgow, following reports a motorcycle had left the roadway and crashed into a tree.

Officers attached to Chifley Police District attended, along with NSW Ambulance paramedics.

Despite efforts to revive the male rider, he died at the scene.

The man is yet to be formally identified, however, is believed to be aged 50.

A crime scene has been established and an investigation into the circumstances surrounding the crash continue.

A report will be prepared for the information of the coroner.

Police are also investigating after a serious crash in the Blue Mountains overnight.

About 11.45pm on Saturday, emergency services were called to the Great Western Highway at Katoomba, following reports a truck had crashed.

Police have been told the truck, carrying newspapers, left the road and crashed into an embankment, spilling its cargo across the highway.

Emergency services worked to free the male driver of the truck, aged 30, before he was treated and taken to Nepean Hospital in a serious condition.

Officers attached to Blue Mountains Police Area Command attended and have commenced an investigation into the circumstances surrounding the crash.

Police are appealing for anyone who may have dash cam footage of the incident to contact Crime Stoppers.

Traffic on the Great Western High is closed in both directions with motorists urged to avoid the area.

For up-to-date traffic information, visit www.livetraffic.com.