Detectives investigating arson attacks on thatched cottages in two picturesque villages have issued descriptions of the suspects.
Firefighters believe the roofs of properties in the Cambridgeshire villages of Brampton and Offord Cluny - where average house prices top £300,000 - were set alight deliberately.
They have warned owners of thatched properties to stay alert after four homes were damaged in the attacks which happened early yesterday.
Area commander Rick Hylton said: "This morning we had five fires caused deliberately that had the potential to both seriously damage property and put lives of Cambridgeshire residents at risk.
"We are working closely with police. However, we're urging residents, and especially those with thatched properties, to be vigilant to any suspicious activity and ensure you have a working smoke alarm."
The first call came at 12.37am to a property in New Road, Offord Cluny.
Crews found smoke coming from the roof but managed to extinguish the blaze.
Firefighters were then called to three similar fires in Brampton.
Cambridgeshire Police said they were linking the incidents to another blaze in Brampton in which some conifer cuttings were set alight and the flames spread to other trees.
Officers are also keeping an open mind as to whether a stack fire in the village's Hemingford Grey is linked.
They are looking to trace two white men aged between 25 and 30.
The first is described as 6ft 4ins to 6ft 6ins, thin and was wearing a dark hooded top and dark trousers.
The second was slightly shorter, stocky, with brown wavy hair and was wearing a grey hooded top and black trousers.
They are thought to have been travelling in a red hatchback with a loud exhaust.
Detective Sergeant Iain Moor, from Cambridgeshire Police, said: "These fires were extremely dangerous and it is fortunate that no-one was seriously injured or killed.
"Luckily these fires were caught early and were extinguished without causing major damage but it goes without saying they could have been a lot more serious.
"I would urge anyone with any information about who is responsible to contact police."
Anyone with information should contact Mr Moor on 101 or Crimestoppers, anonymously, on 0800 555111.