Police have arrested the gunman they believe is responsible for a mass shooting at an Orlando high-rise on Friday morning.

Jason Rodriguez, 40, is in custody and currently being transported to an Orlando jail after gun shots rang out at the building, killing at least one person and injuring at least five others. Police said the man's mother may have turned him in.

He was arrested at her house.

"This is a tragedy no doubt about it, especially on the heels of the tragedy in Fort Hood that is on our minds," Orlando Police Chief Val Demings said. "I'm just glad we don't have any more fatalities or any more injuries than we currently have."

Police said they don't know a motive yet, but Rodriguez told reporters as he was led away in handcuffs that he was trying to get back at the company.

"Why did you do it?" one television reporter asked.

"Because they left me to rot," Rodriguez said.

Orlando Fire Department dispatchers reported a shooting with multiple victims on the eighth floor of the Gateway Center at 1000 Legion Place around 11 a.m. Rodriguez opened fire with a single handgun, sending people running and screaming and barricading themselves in a safe location.

The Orlando Sentinel is reporting at least one person is confirmed dead and five others were transported to the hospital as authorities still sifted through the carnage.

Rodriguez is a former employee at Reynolds, Smith & Hill, a transportation engineering consulting firm. Officials for the company confirmed that the shooting started in their offices, but said they did not know who the person was. He hadn't worked with the company for over a year, reports WESH. Police said all the shooting victims were contained to the one company.

Police went floor-by-floor of the 16-story building searching for the suspect and other shooting victims.

"The building is not secure now," Deputy Chief Mike Droege of the Orlando Fire Department said. "It's still unfolding."

Dozens of police cars and fire engines at at least six ambulances responded to the building shortly before noon amid reports of shots being fired. Still, Rodriguez slipped through the police web before being caught a few hours later.

Mark Vella, who works in a different office on the 12th floor, said he and five co-workers also pulled a filing cabinet in front of their door. They prayed and talked about what to do if the gunman showed up.

"It was a little scary, a little unnerving," Vella said. "We were afraid the guy was still in the building and making the rounds."