Burglars wearing balaclavas raided a house in Riddlesden near Keighley and escaped with a haul of jewellery.
The occupants of the property in Newlyn Road were at home when three men, one carrying a knife, entered the premises at about 7.30pm yesterday.
They demanded jewellery and cash and then searched the house before running off towards Hospital Road.
The suspects are all believed to have been white, spoke with Yorkshire and were wearing Adidas tracksuits.
Detective Inspector Alan Weekes, of Bradford District CID, said: “The suspects made off on foot, but we believe they may have run to a waiting vehicle.
“A silver Audi car was seen driving away at speed towards Granby Lane at around that time and we would like to hear from anyone who may have seen this vehicle in the area at around the time stated.
“We would also be keen to hear from anyone who witnessed any suspicious activity in the Newlyn Road area at around the time this occurred.”
Anyone who can assist the investigation is asked to contact DC 5013 Jones at Bradford District CID on 101, quoting crime reference 13170029680, or report anonymously to the independent charity Crimestoppers on 0800 555111.