A teenage girl fled a New Year bloodbath after climbing through an upstairs window to escape a gunman who shot three female relatives and then himself.
Durham Police said Michael Atherton, 42, shot and killed his 47-year-old partner Susan McGoldrick, her sister Alison Turnbull, 44 and her niece Tanya Turnbull, 24, before turning the gun on himself.
The 19-year-old, named as Laura McGoldrick and thought to be the killer's step daughter, had shotgun pellets removed from her wrist and left hospital on Monday. She is now helping officers piece together what happened afterAtherton went on the rampage in Peterlee, county Durham.
Officers revealed Atherton had a gun licence for three shotguns and three section one firearms, which require extra vetting from the police.
A neighbour reported seeing a man covered in blood, screaming, in the early hours of Monday morning.
"I was walking home from work at quarter past 12 last night and the first thing I saw was a guy running around covered in blood.
"He was shouting 'someone's been shot in the head'.
"I knew the family quite well. No one can believe it's happened."
One woman, who did not want to be identified, told the Press Association: "I always called them Mike and Sue. I am devastated, totally devastated. Two nice people, I did not think anything like this could happen.
"We are all just shocked, just stunned. There are no other words to describe it. I cannot believe that four people died there.
"He (Atherton) was very nice, kind and considerate. We both shared the same drive with our cars and, if he saw you, he would open the gate.
"He was nice, so was she. I have just been taking my cards down and I had a Christmas card from them."
According to the Peterlee Mail police received hysterical phone calls from neighbours late on Sunday evening Durham reporting that shots had been fired at 9 Greenside Avenue in Peterlee.
A spokesman for Durham police said: “The indications are this happened very very quickly. We had a call at 11.45 on Sunday night saying a number of people had been shot.”
Police added they had had contact with the family in 2008.
"We have had contact with the family. We are busy reviewing the exact circumstances around that. There was a report of a male at that address self-harming. That was some years ago. We are researching all of this."