The Monaro Highway is expected to remain closed near Michelago for several hours on Thursday afternoon after a truck crash.
NSW Rural Fire Service inspector Ben Shepherd said the crash involved two trucks. One was carrying 45kg gas bottles and the other sand. The truck carrying sand had tipped over, spilling said on the road.
The crash happened about 10am and was near Baroona Road. It is understood traffic has been banking up in the area.
Authorities are encouraging drivers to avoid the area and to us the Snowy Mountains or Hume highways instead.
Crews are working to clear the area, and there were reports some of the gas bottles were leaking, although these were being made safe.
Two people were taken to hospital with injuries.