Erie, Pennsylvania, authorities have established identities for the person responsible and six of the eight people who lost their lives in a Friday attack, with the coroner's office confirming that seven of those killed shared a family connection with the individual named as the attacker.

Erie County coroner Lyell Cook identified Matthew Stone Sr., 45, as the person responsible. According to Erie Police Chief Rick Lorah, a self-inflicted death occurred at the residence.

Six of those killed have been named: four members of the Stone family — Michelle, 44; Angelina, 24, who had been expecting to deliver a baby that Monday; Jonathan, 19; and Matthew, 21 — along with two women from separate addresses, Lora Roberts, 37, and Twila Tanner, 51.

Two children — a boy aged five and a girl aged one — were also among the dead, the coroner noted, adding that state law did not permit disclosure of their names. Speaking at a gathering held in memory of those who lost their lives, Julius Windham identified the toddler among the victims as his daughter Amarianna. Angelina Stone was identified as the girl's mother as well, and had previously lost a son.

In describing the perpetrator, Windham pointed to his roles as a grandfather and the head of his family.

According to a family friend identified as Eller, Roberts made repeated visits to the home of her niece and neighbor Angelina Stone throughout Stone's pregnancy to provide assistance. Friends described Roberts as a mother of five who had recently become engaged. She had also served on the board of a local organisation dedicated to housing support for people without homes and later volunteered there.

In a July 15 Facebook post about a recent wave of shootings in Erie, Roberts called on the community to address the violence, expressing that life holds deep value and that the level of pain and loss being witnessed was a source of profound grief.

Investigators recovered audio and video from the scene. Lorah described the footage as capturing muffled gunfire from within the residence moments before two women — whom he characterised as visibly distressed — arrived at the door and knocked urgently upon it. The footage also included a final message urging people to check on those they care about and to act with kindness. A person opened fire on individuals who had been moving in the shooter's direction, then withdrew back into the building.

According to Lorah, both Roberts and Tanner — the latter having no family connection to the others involved — lost their lives in front of the property. No statement on a possible motive has come from the police chief, though a reference to mental health as a potential contributing element was offered.

Detectives planned to interview family members and review the mobile devices belonging to the victims found near the property.

Situated roughly 120 miles — around 190 kilometres — to the north of Pittsburgh, Erie occupies that stretch of the state closer to Lake Erie than to the city.

Support for anyone dealing with emotional distress or difficulty coping is available through the Samaritans, who can be reached confidentially on 116 123 across the UK and Republic of Ireland, or via their website for local branch information. Those in the United States who need mental health support — whether for themselves or someone they know — can reach the 988 Suicide and Crisis Lifeline by calling or texting 988, or through online chat at 988lifeline.org. The line is available around the clock, free of charge, with privacy protected throughout. Those located outside these countries can visit www.befrienders.org to locate a helpline operating in their area.