Six prisoners are on their way back to Warrnambool and are being assessed for smoke inhalation after their transport truck caught fire near Panmure on Friday.
Emergency services were called to reports of a smoking prisoner transport van at the corner of the Princes Highway and Bant Street about 4pm.
Acting Senior Sergeant Pam Nix said the prisoners had been in police custody and were being transported to Melbourne when the two operators noticed smoke.
"The two vehicle operators noticed smoke and when they pulled over the prisoners also said they smelt it," she said.
"Once the truck was parked the operators found an engine fire.
"They were able to put it out themselves and CFA Panmure responded quickly for back up.
"One prisoner was taken to Warrnambool Hospital for observations only after complaining of smoke inhalation while the other five will remain in Warrnambool police custody and their transfer date will be rescheduled."
An Ambulance Victoria spokeswoman said paramedics were called to the scene following reports of people suffering smoke inhalation.
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