This article was reproduced with the kind permission
of the British Broadcasting Corporation
30 November 2007, 16:59 GMT
Police and the fire service believe the incidents in Rednal, near Oswestry, are linked and said lives would be at risk if the actions continued.
On Thursday evening seven cars on a garage forecourt were set alight in a "serious" blaze.
And on Wednesday crews were called out tackle fires on a bus and a shed housing a lorry.
A number of police officers and a helicopter were deployed at 1840 GMT on Thursday to try to catch the culprits.
Fire investigation officer John Griffiths said the incidents were a major cause for concern.
"Ourselves and the police are treating this very seriously indeed," he said.
"Apart from the obvious loss to the owners of the property, there's also the added risk in the future if it continues that people's lives could be put at risk."
Crews were called out from Oswestry and Ellesmere to tackle the forecourt blaze, forcing Shropshire Fire and Rescue Service to move engines from other towns to provide cover.
Over the last year there have been several spates of arson attacks in the Oswestry area, Mr Griffiths said.