DENVER (AP) Authorities said the person who would later kill five at a Colorado gay nightclub was on the FBI s radar a day before being arrested for threatening to kill family members, but agents closed out the case just weeks later.

The disclosure by the FBI to The Associated Press creates a new timeline for when law enforcement was first alerted to Anderson Lee Aldrich as a potential danger. Previously it was thought Aldrich only became known to authorities after making the threat on June 18, 2021.

The details of the June 17, 2021, tip to the FBI are not known. But the next day, Aldrichs grandparents ran from their Colorado Springs home and called 911, saying Aldrich was building a bomb in the basement and had threatened to kill them. Details of the case remain sealed, but an arrest affidavit verified by the AP detailed how Aldrich was upset the grandparents were moving to Florida because it would get in the way of Aldrichs plans to conduct a mass shooting and bombing.

The grandparents were concerned about Aldrich even before the 911 call, according to the document, with the grandmother telling authorities she and her husband had been living in fear because of Aldrichs recent homicidal threats toward them and others.

As part of the FBIs probe, the agency said it coordinated with the El Paso County Sheriffs Office, which had responded to the June 18, 2021, call from Aldrichs grandparents and arrested Aldrich, now 22, on felony menacing and kidnapping charges. But about a month after getting the tip, the FBI closed its assessment of Aldrich, who is nonbinary and uses they/them pronouns.

With state charges pending, the FBI closed its assessment on July 15, 2021, the FBI said.

Those charges were later dropped for unknown reasons. Under Colorado law, cases that are dismissed by either prosecutors or a judge are automatically sealed to prevent people from having their lives ruined if they do not end up being prosecuted. Authorities have cited the law in refusing to answer questions about the case but a coalition of media organizations, including the AP, has asked the court to unseal the records.

A spokesperson for the sheriffs office, Sgt. Jason Garrett, declined to comment on the FBIs statement or on whether his agency had any tips about Aldrich before Aldrichs 2021 arrest, citing the sealing law.