A man allegedly killed his girlfriend after becoming suspicious of her activity on Facebook, a court has heard.

Brian Lewis, 31, denies strangling his partner Hayley Jones to death at the home they shared with their four children in the town of Phillipstown, south Wales.

The children found their mother's lifeless body in the living room after Lewis fled the scene during the early hours of March 12, Cardiff Crown Court was told.

Jurors heard that cracks began to appear in the couple's relationship when Lewis lost his job and Jones, 26, found work as a care assistant. At that time, Lewis began socializing on the Web site Facebook, as well.

"Hayley had began spending a lot of time on the internet chat site Facebook. Brian Lewis was to state in an interview and to other people that she had been quite secretive about this," said prosecutor Mark Evans.

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