Police are appealing for witnesses after an attempted robbery at a house in The Boundary, Oldbrook, Milton Keynes.
At 6.30pm on Thursday, an offender was seen by the victim trying to access the porch of her property.
The victim made her way to the front door and saw the offender wearing a black balaclava stood holding what is believed to be a knife.
On being confronted, the offender attempted to grab the victim’s gold necklace from her neck.
The offender and three other men, all wearing black full face balaclavas, ran off.
If you have any information, contact Det Con Scott Dempsey from Milton Keynes police station via the Thames Valley Police Enquiry Centre on 101.