Crews in Sheffield were alerted to a blaze on Southey Avenue, Southey, at 7.40pm on Wednesday and found two wheelie bins on fire.
Three hours later firefighters in the city dealt with a a Volkswagen Passat found burning on Whitehouse Lane, Walkley.
And at 3am on Thursday, a number of tyres were found alight on Southey Green Road, Southey Green.
The night before, Doncaster firefighters spent two hours dealing with a number of tyres set on fire on Armthorpe Lane, Barnby Dun.
Police are appealing for witnesses or anyone with information about the arsonists responsible to call them on 101 or to contact Crimestoppers, anonymously, on 0800 555111.