A local MP says the shooting is not terror-related and the suspect is not on the run.
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 said they believed the incident had now been contained.
Officers appealed to the public not to speculate or share pictures of the scene on social media or anywhere else.
Home secretary Priti Patel tweeted her thoughts were with those affected.
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