A man has been temporarily detained and questioned in the case of an Arizona teenager who vanished in 2019 only to turn up at a police station in northern Montana last week. 

Alicia Navarro, who is now 18, entered the Havre Police Department near the U.S.-Canadian border on July 23. Navarro previously has been described as a high-functioning autistic teen who left her Glendale home in the middle of the night four years ago. 

Days after Navarro identified herself to law enforcement in Montana, a man was detained and questioned by police as his apartment was searched. That individual later was released, according to The Associated Press. 

Garrett Smith, who lives in the apartment next to the one that was searched last Wednesday, told the AP that for at least a year Navarro lived there with the man who was questioned, describing them as quiet. 

MISSING ARIZONA GIRL FOUND SAFE NEAR CANADIAN BORDER AFTER 2019 DISAPPEARANCE 

Arizona woman

Glendale Police Department officials said on Wednesday that Alicia Navarro, who went missing when she was 14 years old, was found safe in a Montana town near the U.S.-Canadian border, according to FOX 10. (Glendale Police Department)

Police spokesperson Gina Winn confirmed to the news agency that a person was temporarily detained as Glendale detectives executed a search warrant in Havre. Three other people in Havre have been questioned, she added, noting that authorities are working to determine what happened over the past four years, whether a crime occurred and if someone could be held accountable. 

Another neighbor, identified by the New York Post as Ron Turner, said Navarro had "covered her whole eyes... with her head down, like she was crying," as the residence in Havre was being investigated. 

"The guy got taken away by the time she came out. Officers were talking to her," he told the New York Post. "They were talking to her and they were over there maybe three minutes and she hung her head and covered her face." 

2 DEAD IN SUSPECTED MURDER-SUICIDE AT BOAT LAUNCH IN NORTHWESTERN MONTANA 

Glendale Police Department press conference

Lt. Scott Waite speaks to the media on Wednesday, July 26, 2023, in Glendale, Arizona, after Alicia Navarro was found safe. Kidnapping is among the possible scenarios for her unexplained disappearance, he said, according to The Associated Press. (AP/Glendale Police)

Turner said three police cars showed up to the building, "and they all got out with guns drawn and went into the apartment" before re-emerging with a man in handcuffs, who then entered a law enforcement vehicle, according to the Post. He reportedly added that armed FBI agents were there as well. 

Jessica Nunez, Navarro's mother, was relentless in searching for her daughter, even as years went by. 

"We are happy, and at the same time, we are hopeful we will be able to supply this family with a little more closure," Glendale Police spokesperson Jose Santiago said last week. 

Havre Police Department Montana

Navarro showed up at the Havre Police Department in Montana on July 23. (Havre Police Department)

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Video provided by police show Alicia Navarro saying, "No, no one hurt me," after police asked if she was harmed.

Fox News’ Adam Sabes and The Associated Press contributed to this report.