Traffic is heavy at the Mooney Mooney Creek bridge after a truck crash.

File image.
File image.

A TRUCK driver has been fined and had his vehicle defected after an M1 crash on Thursday. 

The Mooney Mooney Creek Bridge collision occurred about 5.20pm when the heavy vehicle left southbound lanes and became trapped atop a guard rail. 

The driver, who police said was believed to be in his 30s, underwent a breath test at the scene and returned a negative result. 

He was fined for negligent driving. 

Earlier: Northbound traffic is heavy at the Mooney Mooney Creek bridge after a truck crash resulted in the closure of lanes on Thursday.

Police and emergency services were called to the scene around 5.25pm.

Initial reports indicated the southbound truck had gone through the median strip and entered the northbound lanes, a NSW Police spokesperson said.

The driver is understood to not have been trapped in the vehicle.

Motorists travelling in both directions have been urged to take caution and to expect delays. Diversions around the crash site have been put in place.

All northbound lanes reopened around 6.10pm. LiveTraffic has reported that northbound traffic has queued for around three kilometres.

A NSW Fire and Rescue crew arrived on the scene around 5.45pm where they found the truck was leaking sump oil.

A spokesperson for Fire and Rescue said the truck had come up on the road railing and become stuck. The attending crew rendered the vehicle safe and were still on the scene around 6.17pm.

The crash is the second incident in area after in the past week, after a fiery crash involving a truck and two other vehicles claimed the lives of two people on July 31.