SUNRISE, Fla. — Prosecutors have released hours of video interrogation of Florida's school shooting suspect, footage showing the young man slouching in a chair, being repeatedly urged by a detective to speak louder and punching himself in the face when he is alone.

The video y shows Cruz hunched over at times, leaning back at others. He is seen wearing hospital clothes and speaking so softly at the beginning that Broward Sheriff's Detective John Curcio has to repeatedly urge him to talk louder. At one point shortly after entering a small interrogation room, the detective asks Cruz: "You all right? Got to be able to speak so I can hear you."

At one point, with the police out of the room, the video shows Cruz take two fingers, put them to his left temple and pretend to pull a trigger. He gave a little shake after doing this. Later, he is seen punching himself hard in the face with both hands and occasionally scratching at his right arm with a small object he picked up off the floor.

Much of the interrogation focused on a demonic voice Cruz claims he has heard inside his head for years that urges him to commit violent acts. When asked what the voice usually said, Cruz answered, "Burn. Kill. Destroy." He also said the voice told him to cut himself.

At another point with Curcio out of the room, Cruz mutters, "Kill me," and then, later, "I want to die."

Pinellas County Sheriff Bob Gualtieri told the Marjory Stoneman Douglas High School Public Safety Commission that Cruz's fluctuating behaviour through the years made it difficult for school officials to determine how he should be handled. Cruz, a 19-year-old former student at Stoneman Douglas, is charged with killing 17 people in the Valentine's Day attack there.

"It was really a roller-coaster with Cruz really from birth," Gualtieri said. A report released last week by the Broward County school district said he began showing behavioral issues that got him kicked out of pre-kindergarten. He spent his school years shuttling between regular campuses and those for children with emotional and behavioral problems. "He had some really bad low times but at times he was without behavioral issues," Gualtieri said.

Gualtieri didn't go into details but it has been previously reported that Cruz got into fights, committed vandalism, cursed teachers and drew a swastika on his backpack. Administrators conducted a threat assessment of him in 2016, about five months before he was kicked out of the school.

Cruz is jailed on 17 first-degree murder charges. His attorneys have said he would plead guilty in exchange for a sentence of life in prison without parole. Prosecutors are seeking the death penalty.

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