On the night police say Baltimore tech CEO Pava LaPere was killed, she opened a lobby door of her apartment building for suspect Jason Billingsley before they briefly spoke and got on an elevator together, a warrant reviewed by The Associated Press said.

Billingsley, a convicted sex offender and suspect in other serious crimes, waved the 26-year-old entrepreneur over to the glass door on Sept. 22, records said. At the time, LaPere was sitting on a couch in the lobby of the downtown apartment building. Less than an hour later, surveillance footage captured Billingsley "scrambling for an exit" as he wiped his hands on his shorts and fled the building.

Police have said there’s no reason to believe LaPere knew Billingsley, who was already wanted by multiple agencies for his connection with a targeted rape, attempted murder and arson incident on Sept. 19.

Records: LaPere died of strangulation, blunt force trauma

LaPere's body was found partially clothed on the roof the her apartment building Monday morning by police, hours after she was reported missing, the warrant said. She died from strangulation and blunt force trauma.

It's unclear if Billingsley has an attorney who can comment on his behalf. The public defender's office, which has represented Billingsley in previous cases, did not immediately respond USA TODAY's requests for comment Friday morning.

The court records shed new light on the case that has disturbed the Baltimore business community. LaPere, named on the Forbes' 30 under 30 list for social impact earlier this year, has been celebrated by family, friends and colleagues for her ambitious startups, activism and love for the city of Baltimore.

Before her death Friday night, LaPere had attended a festival recognizing the Baltimore arts community, her friend told The Associated Press.

Grim details in Billingsley's earlier case revealed by court records

Billingsley, 32, was arrested Wednesday night by law enforcement, ending a large manhunt that began on Sept. 20, when the Baltimore Police Department issued a warrant for his arrest after he allegedly entered the apartment of two people in the building where he worked and attacked them.

Police said Billingsley held a woman and her boyfriend at gun point and then tied them up with duct tape before repeatedly raping the woman, according to a warrant. He is also suspected of slitting her throat before setting the couple on fire, leaving them with serious burns, police said. The couple survived.

Police officials said the department did not notify the public about Billingsley after that incident and before LaPere's death, because they had no evidence he would commit "random" acts of violence.

Once Billingsley was identified as the suspect in LaPere's killing, police released a description and urged residents to stay aware of their surroundings.

LaPere's family thanks law enforcement

LaPere’s family thanked law enforcement in a statement Thursday for their “tireless efforts” during the investigation and manhunt.

“We’re relieved to know he can no longer hurt other innocent victims,” the family said. “While this doesn’t change that Baltimore lost one of its most passionate, influential fans, our efforts remain focused on remembering and celebrating Pava Marie — her life, successes, and legacy.”

Contributing: The Associated Press