A father has killed his two young children before taking his own life.
The man, named locally as David Cass, 32, apparently smothered the girls, aged one and three, before hanging himself.
Police sources said that the man had telephoned his wife, from whom he had recently separated, and threatened to kill their children at around 6.45pm last night.
He is said to have told her that he could not bear to live without the girls.
The man, who was in his 30s, had been staying alone in a caravan near the garage where he worked following the breakdown of his marriage.
However, on Friday he resigned from his job at Paynes Road MOT centre in Southampton.
It is understood he had been looking after his two children for the weekend in the caravan. After he called his estranged wife threatening to kill the children, she dialled 999 and police launched an immediate search.
Officers arrived at the MOT centre within minutes, but all three were already dead.
The children's bodies were discovered in the caravan at the back of the garage, and their father's body was nearby.
Much of the road was sealed off last night as forensic officers searched the area looking for evidence.
The garage, which is opposite an infants' school and 100 yards from a parish church, offers MOTs and used car sales. It is closed on Sundays.
The verger of nearby Christ Church, William Green, 49, said: 'I was at church from 6.30 until 7.30. When I came out of the church the whole road was closed off and there were eight police cars and vans and an ambulance parked outside the garage.
'We had heard no sirens and had no idea what was happening all the time we'd been in church.
'This is dreadful. It's absolutely terrible that something like this should happen here. It's so out of character because this is normally a safe area.'
A Hampshire police spokesman said: 'Officers attended the car sales garage at around 6.51pm where they discovered the bodies.
'They are not looking for anyone else in connection with the deaths.
'Officers are currently in the process of tracing and informing next of kin.'
It is understood that the father only recently separated from his wife.
He left the marital home, and was offered a caravan by his employers at the garage as temporary respite.
His estranged wife allowed him to look after their two young daughters there on the weekend.
Police have launched Operation Roselands to investigate the deaths and a post-mortem examination on the three bodies is due to take place later today.