Mugshot of Nikolas Cruz Released as Details on Florida School Shooting Suspect Emerge

The 19-year-old faces 17 counts of premeditated murder.

The mugshot of suspected Florida school shooter Nikolas Cruz has been released as dark details of the teen's life continue to emerge.

The 19-year-old reportedly posted threats to "shoot people with my AR-15" to social media prior to the attack, which left at least 17 dead at Marjory Stoneman Douglas High School in Parkland Wednesday.

At least one student recognized Cruz from an Instagram photo in which he posed with a gun in front of his face, according to CBS News. Another online comment reportedly read, "I wanna die Fighting killing s**t ton of people." 

The teen had been expelled from the high school for disciplinary reasons in the last school year, according to reports. He also associated with a white supremacist group, according to social media posts. 

In November, his adoptive mother, Lynda Cruz, died of complications from pneumonia. Cruz had reportedly since been living with a friend's family in Broward County.

Along with his mugshot, police released a list of charges against Cruz following his arrest: 17 counts of premeditated murder. 

Cruz was booked after police escorted him from a hospital where he'd been treated for labored breathing he had apparently suffered during his arrest.

At a Thursday press conference, the officer who arrested Cruz described the moment he took him into custody. Michael Leonard of the Coconut Springs Police Department said he heard a description of the shooting suspect over his police radio and went to help authorities in neighboring Parkland.

Leonard said he saw a teenager walking alone down a residential street. "He looked like a typical high school student," the officer said. But wearing a maroon shirt and black pants, he matched the clothing description put out by officers at the school.

Cruz made no attempt to escape when confronted by Leonard. He "was taken into custody without any issues," the officer said.

Authorities say Cruz took an Uber to the school of about 3,000 students and was armed. He first pulled a fire alarm in what cops reportedly believe was a bid to increase his kill count.

Students believed the school was conducting a fire drill until shots rang out. In the ensuing chaos, some students, teachers and employees took cover while others fled for their lives.

Seventeen people were killed, including an athletic coach who reportedly shielded students from the bullets. Fifteen victims were also hospitalized.

The shooting ranks among the deadliest in modern U.S. history.