In a rampage which lasted just 12 minutes, Plymouth gunman Jake Davison shot and killed five people before turning the gun on himself.
The events of August 12 last year amounted to one of the worst mass shootings the UK has ever seen.
The 22-year-old first shot dead his mother before leaving her home and killing four others - including a three-year-old girl - in the streets of Keyham.
Questions have since been raised over how Davison came to legally own a shotgun after he assaulted two youths in a park.
The police watchdog is still investigating what happened and multiple members of Devon and Cornwall Police staff have been served misconduct notices.
Here are the details of how the killings in Keyham unfolded - and what has come to light since.
Davison applies for a shotgun certificate for use in clay pigeon shooting.
Devon and Cornwall Police issue Davison with a shotgun certificate valid for five years after processing his application.
Davison legally purchases a pump-action shotgun.
Davison assaults two youths in a park in Plymouth. He admits the offences and attends the voluntary Pathfinder programme.
End of November
A worker on the scheme raises concerns directly with Devon and Cornwall Police’s firearms licensing department about Davison’s possession of a shotgun.
The shotgun and certificate are seized.
Davison completes the Pathfinder scheme.
Following a review by the firearms licensing department, the shotgun and certificate are returned.
August 12 - The day of the shooting
6.11pm: Devon and Cornwall Police receive multiple calls reporting gunshots in Biddick Drive.
In 12 minutes of violence Davison had killed his mother Maxine Davison, 51, Lee Martyn, 43, and his three-year-old daughter Sophie, dog walker Stephen Henderson, 59, and Kate Shepherd, 66. He also injured a mother and son.
6.17pm: Armed and unarmed officers arrive at the scene six minutes after the first call and discover the bodies of those killed.
6.23pm: An entry on the police call log says the body of a man, later identified as Davison, has been found in Henderson Place.
By 9.34pm police say a critical incident has been declared.
It emerges Davison had discussed the misogynistic 'incel' movement online and had 'liked' a series of videos about guns on social media.
Devon and Cornwall Police later confirm they have made a mandatory referral to the Independent Office for Police Conduct (IOPC) about his possession of a shotgun, which begins an investigation.
The Home Secretary joins Chief Constable Shaun Sawyer in paying respects to the victims.
A cousin of Lee and Sophie Martyn pays tribute to the father and daughter. Jess Morcom said Mr Martyn “had the kindest heart and would do anything for anybody”.
Ms Morcom said Sophie’s family had been “truly blessed” to have “seen you grow into such a beautiful, funny and clever girl”.
Mr Washington’s family say their world “has been turned upside down in the blink of an eye”.
The Government announces police forces in England and Wales are being asked to review firearm application processes. Firearms applicants will be subject to social media checks.
It emerges Davison received mental health support during lockdown. Reports have suggested his mother had been struggling to get help for her son.
Two teenage boys are praised as it emerges they saved the lives of bystanders who were frozen with fear during Davison’s rampage.
The National Police Chiefs’ Council launches a review into Devon and Cornwall Police’s firearms licence procedures.
An opening inquest hears Davison launched his shooting spree after arguing with his mother. All five victims died from shotgun wounds.
Around 300 people attend the funeral of Lee and Sophie Martyn.
The IOPC says a member of Devon and Cornwall Police staff involved in approving Davison’s firearms application has been issued with a gross misconduct notice. A police officer who investigated the assault allegations would be issued with a misconduct notice.
The Home Office announces that from November 1 all firearms applications must be accompanied by a medical document signed by a registered, practising doctor.
A pre-inquest review hears Davison’s GP declined to comment on whether he was suitable to hold a firearms licence when asked by Devon and Cornwall Police during the application process.
The IOPC says a third Devon and Cornwall Police employee has been served with a gross misconduct notice.
The watchdog says it is also investigating the claims of a man who says he told police he was assaulted by Davison outside a supermarket in Plymouth in 2016.
Speaking ahead of the six month anniversary of the shootings, IOPC regional director David Ford said the watchdog is drawing its lines of enquiry to a close and preparing its final report.
He said: “I would again take this opportunity to send my sympathies to the bereaved families and those injured in the shootings, with whom we have kept in touch during the progress of our investigation.
"We have been grateful for their continued patience, along with that of the wider community, while we have undertaken our detailed enquiries."
He said the "vast majority" of the IOPC's investigation is complete but the watchdog is waiting for one further document which it expects to have by the end of February.
"This will be considered before we finalise our substantial report," he added.
"In the interim we are drawing remaining lines of enquiry to a close and preparing our final report and conclusions, which we hope we can share with the coroner and Devon and Cornwall Police reasonably soon.
"We will also be deciding whether any of the individuals we served misconduct notices on have a disciplinary case to answer.
“It is vitally important that we, and others, seek to identify what changes could be made to reduce the risk of any repeat of the horrific events of last August.
"As part of our investigation determinations, we will be considering both local and national learning recommendations around firearms licensing procedures.
"When we can issue our full findings publicly will depend on future discussion with the coroner.”