“I have to tell you with a heavy heart that there was a shooting this evening at a neighborhood club. At around 11:57 p.m. [06:57 GMT on Sunday], we received the first phone call that there was an ongoing shooting at the nearby Club Q, according to Colorado Springs Lieutenant Pamela Castro.
Castro announced during a news conference that a suspect was in custody and receiving medical attention for injuries sustained in the attack on Saturday night.
The venue of the incident, Club Q, posted a statement on Facebook expressing its “devastation at the terrible attack.”
“Our prays and thoughts are with all the victims and their families and friends. We thank the quick reactions of heroic customers that subdued the gunman and ended this hate attack.”
In its Google listing, Club Q describes itself as an “adult-oriented gay and lesbian nightclub hosting theme nights such as karaoke, drag shows & DJs”.
The Colorado Springs Police Department will hold a news conference at 8am (15:00 GMT) to give more details on the incident.
The police were yet to provide information on the motivation behind the attack.
Images from the scene after the shooting showed security and emergency vehicles with flashing blinkers parked on a street near the venue.
In 2016, 50 people were killed, including the assailant, and at least 53 were injured in an attack inside a gay nightclub in the US state of Florida, authorities said, in the worst mass shooting in US history.