Five people have died and 25 others were injured after a 22-year-old gunman opened fire with a semi-automatic rifle at a gay nightclub in Colorado, before he was subdued by “heroic” patrons who struck him with his own weapon.

Colorado Springs mayor John Suthers said the attack at Club Q ended when someone grabbed a handgun from the suspect, named as Anderson Lee Aldrich, and hit him with it, before holding him down until police arrived.

The club called the incident a “hate attack”, but investigators are still determining a motive and whether it would be charged as a hate crime.

The El Paso County district attorney said charges against suspect Anderson Lee Aldrich will likely include first-degree murder.

The suspect in the shooting on Saturday night used an AR-15-style semi-automatic weapon, a law enforcement official said.

A handgun and additional ammunition magazines also were also recovered.

The attack ended when a patron grabbed a handgun from the suspect and hit him with it, Colorado Springs Mr Suthers told The Associated Press.

The person who hit the gunman had him pinned down when police arrived, Mr Suthers added.

“Had that individual not intervened this could have been exponentially more tragic,” he said.

On its Facebook page, the club called the incident a “hate attack”. El Paso County District Attorney Michael Allen said investigators are still determining a motive and whether to prosecute it as a hate crime.

Charges against the suspect will likely include first-degree murder, he said.

Police identified the alleged gunman as Anderson Lee Aldrich, who is in custody and being treated for injuries.

Aldrich was arrested in 2021 after his mother reported that he threatened her with a homemade bomb and other weapons, authorities said. No explosives were found, authorities said at the time, and The Gazette in Colorado Springs reported that prosecutors did not pursue any charges and that records were sealed.

Of the 25 people injured at Club Q, at least seven are in a critical condition, authorities said. Some were hurt trying to flee, and it is unclear if all of the victims were shot, a police spokesperson said.

Mr Suthers said there was “reason to hope” that all of those taken to hospital would recover.

The shooting rekindled memories of the 2016 massacre at the Pulse gay nightclub in Orlando, Florida, that killed 49 people. Colorado has experienced several mass killings, including at Columbine High School in 1999, a cinema in suburban Denver in 2012 and at a Boulder supermarket last year.

It was the sixth mass killing this month and came in a year when America was shaken by the deaths of 21 in a school shooting in Uvalde, Texas.

Club Q is a gay and lesbian nightclub that features a drag show on Saturdays, according to its website.

Its Facebook page said planned entertainment included a “punk and alternative show” preceding a birthday dance party, with a Sunday all-ages drag brunch.

Mr Suthers noted that the club had operated for 21 years and had not reported any threats before Saturday’s attack.