A van was torched in Keighley last night only yards from a compound full of double decker buses.
Firefighters stopped flames from the white transit van reaching vehicles belonging to bus company Transdev Keighley and District.
The van, which was set alight around 10.30pm, was in a fenced-off car park at Keighley Plumbers Merchants in Chapel Street.
Watch commander Mark Collingwood, from Keighley fire station, said it was unlikely the flames would have spread to the buses.
But he said: "If we'd got it 10 or 15 minutes later when the whole van was alight possibly it could have damaged the buses.
"We think the likelihood is that the fire was malicious."
A car parked next to the van suffered smoke damage.