(CNN) One of the suspects in a deadly Colorado school shooting pleaded guilty to 17 counts Friday that include murder charges, according to a news release.
Alec McKinney and Devon Erickson face murder charges after police say the two entered STEM School Highlands Ranch near Denver in May and started shooting. An 18-year-old man was killed and eight were injured.
McKinney said he was born a female but was transitioning to male, and he targeted specific students who called him "disgusting" for undergoing that process, according to a probable cause affidavit. His attorneys have said he identifies as male.
CNN has previously referred to McKinney as Alec, but the defendant's legal name is Maya Elizabeth McKinney, according to the office of the District Attorney 18th Judicial District.
On Friday, McKinney pleaded guilty to charges in Douglas County District Court that include first-degree murder in the death of Kendrick Castillo, attempted murder and possession of a weapon on school property, the release said.
McKinney is set to be sentenced on May 18, according to the release. CNN has reached out to McKinney's attorney, but has not heard back.
"Due to changes in Colorado law in 2016 by the state legislature, the mandatory minimum sentence for 16-year-old McKinney is life with possibility of parole after 40 years minus earned time," the release said.
The father of Kendrick Castillo, the 18-year-old killed in the shooting, said he was "shocked" and "pleased" with Friday's guilty plea.
"This is the road to healing for my wife and I," John Castillo said. "I thank God that he entered into a guilty plea and made life a little bit easier on families and ourselves, so we can move onto the next perpetrator."
Charges are still pending against Erickson, the release said.