A four-year-old girl was killed and her mother critically injured when a man shot them before turning the gun on himself.
Police were called to a terraced home in Church Hill, Aldershot, Hampshire, by neighbours concerned about a domestic dispute shortly after 10am today.
They found the young girl with fatal injuries and she died at the scene despite emergency medical care.
The woman was taken to hospital by the Surrey Air Ambulance where she is fighting for her life after suffering a gunshot wound to the head.
The man, whose relationship to the woman and girl is not yet known, was also pronounced dead at the scene.
A Hampshire Police spokesman said a firearm was recovered from the property. He said the incident was "domestic" and police are not looking for anybody else.
A large cordon was in place around the end-of-terrace house just off the main High Street into the town.
Officers have also shut off access to Aldershot Manor Park which is opposite the £250,000 property.
Scenes of crime officers were seen entering the house and a small tent has been erected on the pavement in front.
A young woman has left two small bouquets of flowers at the scene but declined to talk to reporters.
Officers are standing guard at the front and back of the property which has a conservatory in the back garden.
The shooting did not take place in the military area of Aldershot, which has a large British Army base.
Tool shop worker Scott Large said he thought the man who lived there was called Andy, in his 40s, who he thought worked in the building trade.
"I knew the guy and he seemed a friendly, genuine guy who I used to say hello to and he used to be like that with everybody.
"I knew that he lived there with a woman and a child and I thought they were married because they had a kid together, but I don't really know."
Mr Large said he saw a commotion outside his shop at about 9.45 this morning about 100 yards from the house and walked across the busy road to investigate.
"One of the neighbours came up to me and said there had been some form of altercation and not to go near and, the next thing I knew, police and ambulances and the whole lot turned up.
"I really can't believe it. This is a sort of dreary, dozy, quiet sort of place.
"It's a bit grim at this time of year and, if it's true what's happened, then it's given me the heebie-jeebies."Reuse content