(CNN) The man suspected of killing five women at a Florida bank had interactions with police officers in Indiana in recent years after they received concerned calls reporting his desire to kill or harm people, authorities said.

Zephen Xaver, 21, shot all five people execution-style Wednesday at the SunTrust Bank in Sebring, according to an affidavit released by the Highland County Sheriff's Office.

After the shooting, he called 911 and told dispatchers he was in the bank, armed with a handgun and wearing a bulletproof vest, the affidavit said.

"I have shot five people," Sebring police Chief Karl Hoglund quoted him as saying.

Officers found the women lying face down in the lobby with apparent gunshot wounds in their backs and heads. The suspect was barricaded inside, police said.

He allegedly had dreams of killing students

In documents released to CNN by the Bremen Police Department in Indiana, officers detailed previous encounters with Xaver when he lived in the state.

As a 16-year-old student at Bremen High School, Xaver was taken to a behavioral health center in February 2014 after he told a school counselor "he had a dream last night of killing students in a classroom," according to a police report.

He said he had the same dream again during an afternoon nap at school, it said. The investigation is listed as closed after he was taken to the health center.

Bremen Public Schools Superintendent Jim White confirmed Xaver was a student at Bremen High for a short stint during the 2012-2013 school year and returned for a brief period in the 2013-2014 year.

Zephen Xaver

In March 2017, Michigan State Police contacted the Bremen Police Department to report that a female student was getting messages from Xaver saying he was "possibly thinking of suicide by cop" and "taking hostages," the police report said. Officers contacted his mother, who declined police assistance and said she would speak with him, it said.

Xaver entered US Army basic training in March 2016, but left three months later before he completed training, CNN's Barbara Starr reported.

Josh Xaver, an Indiana resident who said he's the suspect's father, told CNN he's "heartbroken for the victims."

"He wasn't raised to be like this. He's always been a good kid. He's had his troubles," the elder Xaver said by phone, without elaborating. "But he has never hurt anyone ever before. This is a total shock."

Zephen Xaver moved to Florida about a year ago, the older man said.

Only one person escaped

The community is mourning the women killed in what authorities described as a "senseless crime."

The victims were a mix of employees and customers, and there's no evidence they were targeted, Hoglund said.

Three of them have been identified. Ana Piñon-Williams, 38, had worked at the bank for a few weeks, her brother-in-law Tim Williams said.

Ana Piñon-Williams.

She was "family to everyone she knew," Williams said. She and her husband had seven children between the ages of 11 and 29, Williams said. She was originally from Mexico and lived with her family in Okeechobee, Florida.

Another employee, Marisol Lopez, 55, and customer Cynthia Lee Watson, 65, were also killed, authorities said. The other two victims, ages 31 and 54, have not been named in keeping with the relatives' wishes, police said.

One bank employee in a back break room heard the shots and ran out the door, and contacted law enforcement, authorities said.

Florida Gov. Ron DeSantis ordered flags to be flown at half-staff throughout the state in honor of the victims.

Suspect is held without bond

Xaver appeared in court Thursday via closed circuit camera and was charged with five counts of capital murder. He was ordered held without bond, and was appointed a public defender because he has no income or assets.

The motive for the shooting remains unclear. The gunman apparently had no plans to rob the bank and had no known connection to anyone there, officials said.

"We believe that it was a random act," Hoglund said. "We do not believe that anybody was specifically targeted."

When he was arrested, Xaver wore a shirt with an artist's rendering of four apocalyptic riders. On the back, it had images of an assault rifle and a scythe.

Police vehicles and ambulances respond to the SunTrust bank branch Wednesday in Sebring, Florida.

"I have been in law enforcement all of my adult life, and this horrific incident shocks and angers me more than anything I have encountered in my career," Highlands County Sheriff Paul Blackman said Wednesday night. "While we still don't know what drove the suspect to commit this heinous act, there is no excuse that can justify the cold-blooded murder of multiple victims."