- Police entered a residence in Aurora, Colorado, after several hours of failed negotiations with the gunman, who had barricaded himself inside.
- The gunman fired shots at police from a second-storey window before he was killed as SWAT officers stormed the building. It is not yet known if officers shot the suspect or if he shot himself.
- Inside the building officers found three other people shot dead.
- One person inside had escaped and alerted authorities.
- Officials notified neighbours of an emergency around 3:00am local time (10:00am GMT) and evacuated several blocks, Aurora police spokeswoman Cassidee Carlson told KUSA-TV.
The fatal shootings in Aurora come six months after a man shot dead 12 people and wounded 58 more at a cinema in the city.
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Officers carried out first aid and paramedics were called to the scene, but the victim was pronounced dead a short time later.