Police have named the man as 22-year-old Jake Davison, who's from the Keyham ((pron: key-um)) area and who had a firearms licence.
Officers say a "very young girl" was one of his victims last night - while two others remain in hospital.
Jim Minhinick lives close to where the shootings happened:
"I heard a bit of a commotion out the back, and helicopters came over and landed in the field. And then there was another helicopter outside hovering. And there were police cars going up and down the street."