A man suspected of killing five people before turning the gun on himself has been named locally as Jake Davison.
Three females and two males were shot in the Keyham area of the city on Thursday evening.
Police said the incident, the worst mass shooting in Britain since 2010, is not terror-related.
Four people died at the scene and one died later in hospital. An MP has said one victim was a child.
Emergency services were called to Biddick Drive shortly after 18:00 BST on Thursday
Devon and Cornwall Police said two females and the three males died at the scene, while one female died shortly after in hospital.
The force added: “The area has been cordoned off and police are not looking for anyone else in connection with the incident.”
Plymouth Sutton & Devonport MP Luke Pollard said the incident was “unspeakably awful” and that he was “utterly devastated” to learn one of those killed was a child.
People were asked to stay inside and follow police advice as the emergency services responded.
Eyewitness Sharron, who lives nearby and did not want to give her full name, said what happened was “horrendous and so sad”.
“Firstly, there was shouting, followed by gunshots – three possibly four to begin with,” she said.
“This was when the shooter kicked in the door of a house and randomly started shooting. He ran from the house shooting as he ran and proceeded to shoot at a few people in the linear park up from the drive.”
She said the “shooter proceeded along Royal Navy Avenue still shooting”.
Scenes of crime officers in white suits could be seen using cameras in the street and members of the public who lived locally were not allowed into their homes, PA Media reported.
Home Secretary Priti Patel tweeted: “The incident in Plymouth is shocking and my thoughts are with those affected.
“I have spoken to the chief constable and offered my full support.
“I urge everyone to remain calm, follow police advice and allow our emergency services to get on with their jobs.”
Source: BBC
