Colorado police mistook an armed homeowner with an intruder and shot him dead, authorities said.

The Aurora Police Department said it was responding to a 911 call about an intruder and heard shots fired from inside a home in the city shortly after 1:30 a.m. local time Monday.

When they went inside to investigate the "chaotic and violent scene", an officer encountered an armed man and shot him, only later to find out that he was the homeowner, the department said in a statement.

Then they found an intruder dead on the man’s bathroom floor, and determined that he had been killed by the homeowner.

The homeowner was rushed to the hospital with gunshot wounds, but later died. The officer who shot him has been placed on administrative leave pending an investigation and no charges have been filed yet in the case, according to KDVR.

"This is a very heartbreaking and tragic situation for everyone involved," Aurora police Chief Nick Metz said. "We are providing assistance through our victim advocates to help the family of the deceased resident through this very difficult time."

A juvenile inside the home during the shootings was hospitalized after suffering serious, but non-life threatening injuries at the hands of the intruder.

The identities of the homeowner and the intruder have not been released.