image captionPolice are responding to a shooting in Keyham in Plymouth
Police in Plymouth have confirmed a "number of fatalities" in a "serious firearms incident".
Devon and Cornwall Police were called to Biddick Drive in the Keyham area at about 18:10 BST on Thursday.
The force said: "There have been a number of fatalities at the scene and several other casualties are receiving treatment."
Plymouth Moor View MP Johnny Mercer tweeted it was "not terror related" and the suspect was not on the run.
Police declared a critical incident but said they believed it had now been contained.
Officers appealed to the public not to speculate or share pictures of the scene on social media or anywhere else.
image sourceSnapchatimage captionMultiple air ambulances have attended including from Devon and Cornwall
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."
'Randomly started shooting'
Eyewitness Sharron, who lives near Biddick Drive 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".
Another witness, Robert Pinkerton, said he "walked around the corner" and "bumped into a bloke with a shotgun". He said the man was dressed all in black.
At the scene
Scott Bingham, BBC South West
image captionFour air ambulances have been seen taking off from the scene
I'm standing on Wolseley Road, one of the main routes through Plymouth and it is currently closed in both directions around Henderson Place with traffic being diverted.
There's a huge police presence here, I've lost count of the number of police vehicles.
Just where I'm standing I can see at least half a dozen.
There are three ambulances and we've just seen four air ambulances actually take off from the scene here, so there's a huge amount going on.
People are being asked to stay inside and follow police advice as the emergency services respond.
Local MP Luke Pollard said the situation "looks very serious indeed".
He later tweeted: "Update: awaiting confirmation of number of victims but this looks like a very grim day for our city and our community.
"Please can I ask that you think of the families and our community and not share any images or videos of any of the victims. #keyham."
Really worrying news coming out of Keyham in #plymouth. Please can everyone stay safe, stay indoors and follow police advice.
— Luke Pollard MP (@LukePollard) August 12, 2021
The BBC is not responsible for the content of external sites.View original tweet on Twitter
Labour leader Sir Keir Starmer tweeted: "There's much we don't know about the shocking events in Plymouth. However it's clear tragedy has hit Keyham.
"My thoughts are with the families and neighbours of those caught up in this nightmare. I pay tribute to our emergency services who ran towards events we'd all run from."
Mr Pollard added Ford Primary School and St Mark's Church on Cambridge Road would be open from 09:00 on Friday as a "safe place for our community to come together".
image captionEmergency services are at the shooting in Plymouth