Emergency services launched a major operation and set up an exclusion zone after the incident in Glasgow city centre.
Crews fought to bring the flames under control - just yards from Buchanan Galleries.
It is not clear how the fire started but the vehicle burst into flames shortly before 9am.
Firefighters raced to the scene in North Hanover Street, at Cathedral Street, after the alarm was raised this morning.
A Scottish Fire and Rescue spokeswoman said: “We received a report of a fire in North Hanover Street, Glasgow, at 8.47am today.
“Crews have been called to the scene.”
There is no indication of injuries.