Three masked men threatened an elderly couple and demanded cash during a raid at a house in Dronfield.
The robbers struck at a house in Bents Lane at lunchtime yesterday before leaving in a small, dark blue car.
Derbyshire Police said the victims required hospital treatment after their ordeal.
A force spokesman said: "At lunchtime on Wednesday, June 28, three masked people went into a house in Bents Lane and threatened the elderly couple inside, demanding money.
"The gang was in the house for some time, leaving at 1.50pm in a small, dark blue car which travelled along Bents Lane toward Holmesdale Road.
"The couple required hospital treatment following the ordeal.
"We are appealing for any witnesses to the incident, or anyone who may have been in the area at the time and seen the suspects or car, either before or after the crime.
"We’re also asking drivers travelling along Bents Lane to check their dashboard camera footage, as it may have captured the car or the gang outside the house."
Witnesses or anyone with information should call Derbyshire Police on 101 and quote reference number 17000273575.
Crimestoppers can also be contacted, anonymously, on 0800 555 111.