Officers investigating the deaths of Arthur Wilson, 65, and his wife, Shirley, 61, said the couple may have known their killer. When police arrived at their bungalow in Bramford, near Ipswich, the doors were locked, there was no sign of a break-in and money had been left inside the property.
Acting Superintendent Peter Worobec said Mr Wilson, a former manager of Ipswich railway station, was bound hand and foot before being strangled. Mrs Wilson was not tied up, but she was found strangled in the living room of the bungalow.
"There were no signs of a struggle to any extent," he said. "One theory is that they let someone in that they knew ... some cash was found in the house that was not well hidden, so the motive does not seem to be theft."
Mr and Mrs Wilson had two daughters and a son, all married. It is understood they called police after failing to contact their parents.
Supt Worobec said he believed the murders took place between 10.30am and 8pm on Monday.