Police investigating an aggravated burglary are urging people to help them catch four Eastern European men involved in an incident in Isleworth last Wedensday (January 8).
The suspects described as white are believed to have forced their way into an address in Northumberland Gardens around 6.30pm and were armed with long screwdrivers.
They assaulted an elderly couple inside and stole an expensive and unique necklace.
Two suspects - an older and younger man - are believed to have been knocking door to door to do odd jobs in recent months.
Police want to hear from anyone who might have heard or seen anything or have private CCTV footage that may assist officers in their enquiries.
Call 020 8247 6650, quoting CRIS 0500517/14, or ring CrimeStoppers on 0800 555111.