Law enforcement personnel gather near the scene of the shooting in Aurora, Illinois.

Five people were killed and seven others injured when a gunman who was being terminated from his job at a manufacturing warehouse in Aurora, Illinois, opened fire on employees, police said.

The gunman, identified as 45-year-old Gary Martin, was killed in a shootout with officers, Aurora Police Chief Kristen Ziman said. He had worked at the company for 15 years and was fired on Friday, she added.

Police, firefighters, and ambulances responded in force Friday afternoon to the Henry Pratt Company warehouse, a 29,000-square-foot building in an industrial park. Multiple 911 calls reported the shooting at 1:24 p.m. local time, and officers arrived in four minutes. Around 2:30 p.m., SWAT officers were seen entering the building. By 3 p.m., the city of Aurora said the gunman had been neutralized.

Five employees of the company were found dead inside the building, Chief Ziman said.

"It cannot be overstated that those people did not deserve this," she said. "Their families have our support."

Five of the officers who responded were also wounded by gunfire within the first five minutes of the incident, Ziman said. They were expected to survive their injuries. Another officer injured his knee in the response, and one employee was also being treated for a non life-threatening gunshot wound.

The Illinois Fraternal Order of Police praised the Aurora Police Department officers who were part of the initial response to the shooting.

"These four heroes willingly ran into harm's way to protect their fellow citizens and very nearly paid the ultimate price," a statement from the police union said.