An elderly man was threatened by three men wearing masks before they raided his home in Terrington St Clement.
Police are appealing for information following the burglary, which happened at about 2am yesterday (Tuesday, January 2) at an address in the Market Lane area.
Officers say the man was alerted to banging at the front door of his property and when he answered it, he was threatened by three men wearing masks.
The men then entered the address and stole cash before making off.
Det Con Nichola Lane said: “This is an unusual incident where three people have attended the property in the early hours of the morning and targeted a vulnerable man in his own home.
“I would like to reassure the community that officers will be conducting extra patrols in the area and residents are reminded to be vigilant.
“I am keen to hear from anyone who may have seen any suspicious activity in the Market Lane area at the time of the incident.”
Anyone with information should contact Det Con Nichola Lane at King’s Lynn CID on 101.
Alternatively contact Crimestoppers anonymously on 0800 555 111.