Two truck drivers have been killed in a fiery head-on collision in Sydney's west.
Both semi-trailers, including one carrying a load of bricks, burst into flames following the crash on Lenore Drive at Erskine Park about 1.30pm on Thursday.
Firefighters used foam to contain the blaze, a Fire and Rescue spokesman said.
Bystander Matt Smith told the Seven Network the crash sounded like an explosion.
"It just sounded like I was in the middle of a battlefield," he said.
The drivers haven't been formally identified and their ages remain unknown, police say.
It is also not yet known how the crash occurred, although authorities say one semi-trailer may have crossed over the median strip and ploughed head-on into the other.
"It's a pretty horrific scene and will need to be processed before we can figure out exactly what's happened," Inspector Simon Maund told reporters.
"This is a reminder of how fragile life is, especially on big roads."
Lenore Drive between Erskine Park and Wallgrove Road remained closed as crash investigators examined the scene.
Police are investigating whether vehicle fault or driver fatigue may have caused the incident.
