A fire on provincial property in Ancaster caused heavy damage early Saturday, officials say.

Around 4:45 a.m., fire crews were called about a fire in a garage used by highway maintenance crews at 1389 Wilson Street East in Ancaster.

When they got there, firefighters found a sanding truck fully engulfed in flames and heavy smoke conditions.

Additional crews were called in to help, and the fire was extinguished. Paramedics treated one worker at the scene for smoke inhalation.

Damage is estimated to be around $1 million, said fire official Dave Christopher.

"Apparently one of those trucks alone is worth a quarter-million dollars," Christopher said.

The cause of the fire hasn't been determined, and the Ontario Fire Marshal has been called in to investigate.

Hamilton police had deemed the fire suspicious, but Christopher said that wasn't the case.

"When the damage is over $500,000 on provincial property, the Fire Marshal's office gets called in regardless," he said.

The investigation is ongoing.