Denver - Four people were killed in a shooting at a house in Aurora, a city in the US state of Colorado, with the suspect still at large, police said.
On Sunday, the Aurora Police Department (APD) said it received a report of a shooting at the house downtown at roughly 2am, reports Xinhua news agency.
Officers found four adults – three men and one woman – dead from gunshot wounds when they arrived three minutes later.
The suspect was identified as Joseph Castorena, 21, supposedly the domestic partner of the woman killed in the house.
A relative of the dead woman told local MSNBC 9 news channel that it was an ambushed shooting.
The suspect hid in the house and opened fire when the victims returned from a party.
Shortly after the shooting, a reverse 911 alert was issued in a 1.5km radius for all residences to shelter in place, while officers searched the neighbourhood in the dark.
The APD classified the investigation as a homicide case but warned the suspect was dangerous and might have a gun.
The Colorado Sun reported that a restraining order had been issued earlier in the week, barring the suspect, 21-year-old Joseph Mario Castorena, from coming to the home or contacting his domestic partner, who lived there.
Police searched Castorena’s home a few blocks away from the site of the slayings but did not find him, the Colorado Sun reported.
Police used drones to search for Castorena at sunrise and were looking for him in the immediate neighbourhood on Sunday.
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