Terrified occupants fled their home as three men broke into their property.
The incident happened at a house in Lancaster on New Year’s Day.
It happened at around 11pm when the trio, who wore balaclavas and spoken with Liverpool accents, smashed a window to the rear of a property on West Road.
The occupants ran off in fear and the offenders searched the house, taking an iPhone and an amount of cash.
Det Con Gill Topping from Lancaster CID said: “I would like to reassure local residents that we believe this was a targeted, isolated incident and there isn’t thought to be any kind of threat to the public.
“The occupants of the house are understandably shaken up by the incident and I would urge anyone who thinks they might be able to help to speak to us.”
Anyone with information can call Lancaster CID on 01524 596456 or 101, quoting incident reference 1689 of January 1st 2018.
Alternatively independent charity Crimestoppers can be contacted anonymously on 0800 555111 or online at crimestoppers-uk.org.