A man shot and killed three people in a home in Colorado on Tuesday before turning the handgun on himself and committing suicide, authorities said.
Sergeant Tim Schwartz of the Weld County Sheriff's Office said police received a call from the home in a community about 35 miles north of Denver before dawn and heard a female voice say "No, no, no" before multiple gunshots were fired.
A man then came on the line and said he was going to kill himself, and the dispatcher heard another gunshot, Schwartz said.
Officers found the bodies of two females and two males, and recovered a handgun at the scene, Schwartz said. Three of the dead were adults, he said, adding that one of the females may have been a teenager.
Schwartz said authorities were still trying to determine a motive for the shooting.
Earlier this year, a gunman in Colorado killed 12 people and wounded 58 others at a midnight screening of "The Dark Knight Rises" in a suburb of Denver.
According to a May report by the Washington, D.C.-based Violence Policy Center, Colorado was one of 10 states where gun deaths outpaced motor vehicle deaths in 2009.