(CNN) -- A barricaded gunman and three people were found dead in an Aurora, Colorado, home after police exchanged fire with the gunman to end a standoff Saturday, authorities said.
A woman earlier escaped uninjured from the home and told police she saw three apparently lifeless people inside, authorities said. She said the man was firing shots inside the residence before 3 a.m., police said.
During a subsequent standoff, the gunman behaved "very irrationally," hung up the phone on negotiators, and ignored bullhorn commands to exit the premises, authorities said. Tear gas did not faze him, they added.
"The male was given multiple commands to come out of the house both on the phone and from a bullhorn outside. He did not comply," Sgt. Cassidee Carlson said in a statement.
Five hours into the incident, a SWAT team in an armored vehicle broke out a house window, and the gunman fired upon the vehicle, without injury to the officers, police said.
Police didn't return fire at the time.
An hour later, the gunman fired upon officers from a second-floor window, but this time, police returned fire, striking the suspect, authorities said.
No officers were injured.
Police entered the residence and found the gunman dead in the upstairs bedroom, authorities said.
Police also found two men and a woman -- all deceased -- inside the home, authorities said. "We do believe that they all knew each other, possibly related. It's unclear if they all lived at the home or what the status of that is," Carlson told reporters.
After being told of the "lifeless bodies," officers, when talking by phone with the suspect during the standoff, did not hear any noises or screaming that led them to believe anyone else inside was alive, she said. No shots were fired after police arrived until officers were fired upon, according to Carlson.
The officers who fired their weapons were placed on paid administrative leave pending an internal review of the incident, police said.
Police weren't releasing the names of the victims or gunman Saturday afternoon.
Aurora was the scene of a mass shooting last July when a gunman killed 12 people and injured 58 more in a movie theater as they watched a midnight screening of the Batman film "The Dark Knight Rises." James Holmes, the 25-year-old man accused in that incident, faces 152 charges, including murder and weapons offenses.