Two train drivers have died after their locomotive derailed in a horror crash at a level crossing near the South Australia-New South Wales border.

The Pacific National freight train reportedly collided with a truck on the Barrier Highway at Bindarrah about 10.30am local time on Sunday.

“The impact of the crash caused the locomotive to catch fire and several train carriages to derail, blocking the entire highway,” SA police said.

The two drivers, a 47-year-old man and a 57-year-old man, both from Port Augusta, died at the scene.

The truck driver, a 75-year-old Queensland man, was taken to Broken Hill Hospital with minor injuries.

A spokesperson for the company confirmed two of its Port Augusta train crew were killed in the crash.

“Pacific National takes the safety of its employees very seriously and has notified regulators who are investigating,” the spokesperson said in a statement.

“This incident is having a profound impact across the organisation, and our first priority is to ensure the highest level of care to the families of our drivers who have tragically died.”

Tweet from @DFIT_SA

The Australian Transport Safety Bureau said it had commenced an investigation into the incident and was deploying Adelaide-based transport safety investigators with experience in train and railway operations to the scene.

“As part of their evidence collection activities, investigators will examine the level crossing infrastructure and rolling stock, interview involved parties and any witnesses, examine truck and train operational information, recover any relevant components for further examination at the ATSB’s laboratories in Canberra, and analyse any recorded information,” the bureau said in a statement.

A report detailing the investigation’s findings will be released to the public at its conclusion.

Motorists travelling between NSW and South Australia are facing heavy disruptions with the major highway connecting the two states closed in both directions.

Police said the road was likely to remain shut for some time.

Motorists coming from NSW will not be able to travel past Broken Hill on the Barrier Highway into SA.

Motorists travelling east will not be able to travel past the Petersburg Road-Peterborough turn-off, about 220 kilometres from the border.

NSW authorities said if people needed to travel, they could take the Silver City and the Sturt highways instead but that would add at least two hours to the journey.

-AAP