Neighbours have told of their disbelief at the deaths of a heavily-pregnant policeman's wife and their young son.
Six-year-old Sam and Lucy-Ann MacMartin were found at their house in Longton, near Preston, Lancashire, after neighbours raised the alarm.
Mrs MacMartin, who was seven months pregnant, was married to a Lancashire Police traffic officer named Gary.
One man, who asked not to be named, said: "They were a lovely, wonderful, family. This is a great shock to us and a great shock to immediate neighbours of the family. We all sympathise with Mr MacMartin."
Sam was described as a "lovely, lively little boy" by his teachers at Longton Primary School.
They added: "This tragedy has shocked our whole school community. Our thoughts are with his family and friends at this very sad time."
Chief Supt Paul Harry of Lancashire Constabulary said: "This is obviously a personal tragedy for Gary and not surprisingly he is still coming to terms with his tragic loss.
"Our main concern must be for his for his welfare and he is being supported by friends, colleagues and our welfare staff."
Friends earlier arrived at the house in Orchard Lane with flowers but the street was cordoned off by police.
Post-mortem examinations are being carried out to establish the cause of deaths. It is believed police are not looking with anyone else in connection with what appears to be a murder and suicide.