Firefighters spent over an hour last night dealing with a blaze which was started deliberately behind a Doncaster post office.
A crew from Doncaster Fire Station was called out to what officers described as a large rubbish fire, at Balby Road.
They were called out to the scene at 10.55pm and did not leave until 12.30am because of the scale and nature of the blaze.
“It is believed to have been deliberately started,” said a spokesman.
Fire chiefs in South Yorkshire have previously warned lives could be lost as a result of arson attacks.
Bosses say malicious fires can mean crews have to diverted from more serious blazes - and in the past a girl died in Sheffield due to the nearest crews being tied up tackling an arson.