Police are appealing for witnesses following a robbery at house in Ashington on Monday July 9.
At 12.30am three masked men broke into a house while the occupants - a couple in their 60s - were asleep.
The offenders assaulted the couple with a weapon causing minor injuries and forced them to open their safe.
A large quantity of cash was taken and the three offenders got away.
Two of the suspects are described as black but all three offenders had their faces obscured by scarves.
Detective Sergeant Alex Lowe said: “This is a particularly nasty crime. The victims were at home in a quiet rural part of West Sussex and were attacked at night and assaulted. I urge anyone with any information about this matter to contact West Sussex CID and quote Operation Markfield or alternatively Crime Stoppers on 0800 555111.”