The Pacific Highway has been closed at Hornsby after a fatal crash involving a truck and pedestrian.
Emergency crews were called to the intersection of Peats Ferry Road (Pacific Highway) and Bridge Road at Hornsby on Tuesday afternoon after reports of a crash.
The NSW Police said initial inquiries indicated a truck had struck a person, who died at the scene.
The truck driver is assisting police with their inquiries and was taken to Hornsby Hospital to undergo mandatory testing.
The Pacific Highway is closed in both directions, with traffic diverted via local streets around the crash site.
A spokesman for the Transport Management Centre said traffic was heavy in the area and motorists should allow extra travel time.
He also said the diversions around the crash site were delaying buses by up to 15 minutes.