A woman had her home in Buttermere near Tring Road, Aylesbury, burgled by four men on Friday.
Property including Asian jewellery was stolen from the home at around 2.40pm.
The men, three of whom were Asian and one who was white, fled the scene after they were discovered by the female homeowner.
Detective constable Nicholas Hills said: “This was a very frightening attack on a woman in her own home in the middle of the day. We would urge anyone who may have seen anything to contact us as soon as possible.”
Anyone with any information is asked to contact Mr Hills on the non-emergency number 101.
You can also contact the independent charity Crimestoppers anonymously on 0800 555 111 or online at crimestoppers-uk.org