Lancashire Police have launched an investigation after an arson attack in Preston.
The incident happened last Friday afternoon when offenders approached a doorway of Lincoln House in Arundel Place, Preston, and poured petrol through a letterbox.
The offenders then set the petrol alight before making off from the scene.
Detective Constable Andy Forsyth, of Preston CID, said: “This was a serious incident and it is only a matter of luck that no-one was seriously injured.
"I would appeal for anyone with information to contact us on 101 quoting log number 721 of October 5th or independent charity Crimestoppers on 0800 555 111."