Gunman kills 5 wounds at least 5 in an industrial facility in Aurora, Illinois.

Updated at 23:53 ET

A man armed with a handgun entered Friday afternoon into Henry Pratt's company in Aurora, Illinois, and killed five civilians, officials said at a conference of press. Five police officers were also injured.

Police chief Kristen Ziman said that the gunman, identified as Gary Martin, had been killed in a shootout with agents. She said, at a second press conference held late at night, that the shooter was a 15-year-old company veteran who was fired on Friday. Ziman said that she did not have any more information on what could have motivated the shooter.

Martin is thought to have acted alone, she said. A search of his home did not allow him to find more information or other weapons. "At that time, I am told that we have found nothing," Ziman said.

Two of the injured officers were airlifted to trauma centers in Chicago, Ziman said. A sixth officer injured his knee.

According to earlier reports, several civilians were reportedly injured in the incident, but at his second press conference, Ziman said that there was only one that had been treated for injuries that do not put his life in danger.

A local hospital reported three people involved in the shootings were being treated for life-threatening injuries.

The names of the deceased have not been disclosed while their families are being notified.

Ziman said the police department had started receiving several 911 calls about a shooter at the factory around 1:24 pm. local hour. Four minutes later, a small group of officers had arrived in the 29,000 square foot building "and was immediately fired upon".

The shooter continued shooting at additional police officers as they reacted on the scene. Meanwhile, other officers began to locate the victims by shooting inside the huge building.

"My heart goes to the victims and their families who just went to work today like any other day," Ziman said.

The gunman allegedly fired at his work site before the police arrived and then hired the first responders in an initial firefight, injuring two police officers before retiring to the huge building to hide.

Thirteen teams of interveners entered the building to find him.

About 90 minutes after the first exchange of fire, the police found the gunman inside and shot him. He was carrying a Smith and Wesson handgun, Ziman said.

Illinois Governor JB Pritzker, who was also attending the press conference, cried the victims killed in Friday's violence – a day after the anniversary of a massive shootout in a high school from Parkland, Florida. "Tomorrow, the families of the victims will be just one more, they join a group that should not exist and continues to grow," Pritzker said.

Similarly, the mayor of the Aurora, Richard Irvin, commented on the omnipresence of mass shootings in the United States. "It is unfortunate that mass shots like this have become commonplace in our country," said Irvin. "It is unfortunate that a cold, heartless delinquent is selfish enough to think that he has the right to live an innocent life." But we, as a society, can not let these horrific deeds to become commonplace ".

Chris Southwood, president of the Fraternal Police College of the State, expressed his gratitude for the courage of the Aurora police officers. "Every policeman dreads days like this," he wrote in a statement. "Yet, these … brave Aurora officers and their colleagues have not hesitated to put their lives in danger today to end further bloodshed."

"These … heroes have voluntarily met the danger of protecting their fellow citizens and have almost paid the ultimate price.We, the Illinois, should be humbly grateful for their sacrifice, and we ask you to join us in praying for a full and rapid recovery, "he added.

John Probst, who claimed to be an employee of Henry Pratt, told ABC7 of Chicago "that a man who worked there" got angry "and was armed with a gun."

Probst said that he had fled the building after hearing gunshots and seeing at least one person bleeding.

This is a story in development. Some things that are reported by the media may later prove to be wrong. We will focus on the reports of police and other authorities, credible media outlets and journalists on the scene. We will update as the situation evolves.

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