Victims’ families have called the Colorado Springs nightclub killer a “monster” who hunted down LGBT+ patrons in a calculated attack last year that killed five people, as the attacker was sentenced to life in prison after pleading guilty to murder and other charges.

Anderson Lee Aldrich admitted five counts of murder and 46 counts of attempted murder. Aldrich also pleaded no contest to two hate crimes, one a felony and the other a misdemeanour.

“This thing sitting in this court room is not a human, it is a monster,” said Jessica Fierro, whose daughter’s boyfriend was killed at Club Q. “The devil awaits with open arms.”

The guilty plea came seven months after the shooting and spares victims’ families and survivors a long and potentially painful trial.

People in the courtroom wiped away tears as Judge Michael McHenry explained the charges and read out the names of the victims.

“You are targeting a group of people for their simple existence,” said Judge McHenry.

“Like too many other people in our culture, you chose to find a power that day behind the trigger of a gun, your actions reflect the deepest malice of the human heart, and malice is almost always born of ignorance and fear.”

The father of a Club Q bartender said Daniel Aston had been in the prime of his life when he was shot and killed. “He was a huge light in this world that was snuffed out by a heinous, evil and cowardly act,” Jeff Aston said. “I will never again hear him laugh at my dad jokes.”

Daniel Aston’s mother Sabrina was among those who said they would not forgive the crimes.

Another forgave Aldrich without excusing the crime.

“I forgive this individual, as they are a symbol of a broken system, of hate and vitriol pushed against us as a community,” said Wyatt Kent, Aston’s partner.

“What brings joy to me is that this hurt individual will never be able to see the joy and the light that has been wrought into our community as an outcome.”

Aldrich mostly looked down as the relatives spoke, glancing sometimes at a screen showing photos of the victims.

“I intentionally and after deliberation caused the death of each victim,” Aldrich told the judge.

The guilty plea follows a series of jailhouse phone calls from Aldrich to the Associated Press expressing remorse and an intention to face the consequences for the shooting.

Several survivors said prosecutors had notified them that Aldrich, who is non-binary and uses they and them pronouns, would plead guilty to charges that would ensure a sentence of life behind bars.

Aldrich was originally charged with more than 300 state counts, including murder and hate crimes. The US Justice Department is considering pursuing federal hate crime charges, according to a senior law enforcement source.

The attack at Club Q came over a year after Aldrich was arrested for threatening their grandparents and vowing to become “the next mass killer”, but those charges were ultimately dropped.

Victims’ family members and survivors spoke at Monday’s hearing about how their lives were forever altered by the terror that erupted just before midnight on November 19 when Aldrich walked into Club Q and indiscriminately fired an AR-15-style semiautomatic rifle.

The line to get through security early on Monday snaked through the large plaza outside the courthouse as victims and others queued up to attend the hearing.

Aldrich had hinted at plans to carry out violent attacks at least a year before the Club Q assault. In June 2021, Aldrich’s grandparents told authorities they had been warned not to stand in the way of a plan to stockpile guns, ammo, body armour and a homemade bomb. Aldrich was then arrested after a stand-off with SWAT officers that was livestreamed on Facebook.

Those charges were thrown out in July 2022 after Aldrich’s mother and grandparents, the victims in the case, refused to cooperate with prosecutors, evading efforts to serve them with subpoenas to give evidence, according to court documents unsealed after the shooting.

Other relatives told a judge they feared Aldrich would hurt the grandparents if released, painting a picture of an isolated, violent person who did not have a job and was given 30,000 dollars (£23,000) that was spent largely on the purchase of 3D printers to make guns, the records showed.

Aldrich was released from jail then and authorities kept two guns — a ghost gun pistol and an MM15 rifle — seized in the arrest, but there was nothing to stop Aldrich from legally purchasing more firearms, raising questions immediately after the shooting about whether authorities should have sought a red flag order to prevent such purchases.

El Paso County Sheriff’s Office said it would not have been able to seek a court order stopping Aldrich from buying or possessing guns because the 2021 arrest record was sealed after the charges were dropped. There was no new evidence they could use to prove that Aldrich posed a threat “in the near future”, the sheriff’s office said.

Investigators later revealed that the two guns Aldrich had during the Club Q attack — the rifle and a handgun — appeared to be ghost guns, or firearms without serial numbers that are homemade and do not require an owner to pass a background check.

Aldrich told AP they were on a “very large plethora of drugs” and abusing steroids at the time of the attack. When asked whether the attack was motivated by hate, Aldrich said only that was “completely off base”.