Two of the new 'scan and go' yellow bikes available to hire in Sheffield have been set on fire by vandals.
The bikes were found burning on Purbeck Road, Waterthorpe, at 10.10pm yesterday.
Firefighters were called out to extinguish the flames.
The bike hire scheme was launched in Sheffield earlier this month, with a fleet of 1,000 bikes available to hire for 50p for 30 minutes.
Users download a free app to locate and unlock a nearby bike and they can be locked up again anywhere in the city when they are finished with.
Company 'ofo' already runs schemes in Cambridge, Oxford, London and Norwich.
A number of the bikes have been damaged in Sheffield, with incidents reported to South Yorkshire Police in the first few days of the scheme being launched.
But ofo said a 'tiny minority' will not ruin the scheme.
Adam Rose, Operations Manager for ofo in Sheffield, said: "We regret that a fire engine had to be called to deal with this senseless act of vandalism. The incident has been reported to the police and we will be assisting them with their inquiries.
"There has inevitably been a small amount of misuse of our bikes, but levels of vandalism are low and the vast majority of our fleet in Sheffield is being used in a responsible and considerate manner. When misuse does occur we have a dedicated team of marshals on the ground to respond swiftly.
"Our launch in Sheffield has proved a huge success and we’re encouraged by how popular the bikes have been with locals."
Anyone with information should call South Yorkshire Police on 101.