Firefighters were attacked by a gang of youths when they were called to deal with a blaze in Greenock.
Missiles were thrown at the crew as it worked to put out fires in bins in Angus Road, in the Larkfield area, on Sunday night.
They were forced to retreat until police arrived and they finally put out the fires at about 2300 BST.
No members of the emergency services were injured and there was no damage to fire or police vehicles.
Investigations are continuing.