Police are appealing for information after a large amount of cash was stolen during a distraction burglary in Dronfield.
Two men visited a house in New Road, Apperknowle, at about 8.15pm last night (Tuesday).
They asked the homeowner if they could come inside and check the taps, to see if the water contained any blue dye.
A short time after their visit, the 85-year-old victim noticed that a safe containing a substantial amount of money had been stolen.
One of the offenders was white, aged about 40, around 5ft 4ins, of average build, and was wearing a grey cap.
The second was aged about 18, about 5ft 5ins tall, of slim build and was wearing dark clothing.
Police want to hear from anyone who saw men matching those descriptions in the area, or who might know the people responsible.
Anyone with information should call Derbyshire police on 101, quoting crime reference 24268/15, or alternatively, Crimestoppers anonymously, on 0800 555 111.