An employee of an armed security company opened fire on a co-worker inside the business Monday morning before fatally shooting himself outside amid what police described as an "ongoing domestic situation."

Moorestown police Lt. Lee Lieber said 42-year-old Edgar Figueroa killed himself after shooting 31-year-old Melvin Nieves four times. Both are from Philadelphia.

Nieves was in critical condition Monday afternoon at Cooper Hospital in Camden. He was conscious when he was airlifted to the hospital, Lieber said.

Lieber said the shooting began in a work area at Shields Business Solutions at around 7 a.m. when the two men had a conversation upon arriving for work. "It was determined that the shooting was sparked by an ongoing domestic situation," he said, without elaborating.

The victim was shot as he ran away from the gunman, who then shot himself in the area behind the building's rear parking lot, Lieber said.

He said only one of the men had a weapon, and the shooting was being investigated as an attempted murder-suicide. No one else was injured.

"None of the employees had any weapons at the time this occurred. They check them in and out, except for the one subject who was deemed the shooter," Lieber said.

Lieber said Nieves had worked for about a year for the company, which provides armored car, ATM and security services.

The company said that it will have a grief counselor available at its offices to provide support for its employees.

"An unspeakable tragedy unfolded here this morning and, first and foremost, we'd like the families of those involved to know that our thoughts and prayers are with them," the company said in a statement. "To our employees, we want to reiterate that their safety is our absolute priority."

The office is located in a business park and is less than a mile away from the Moorestown police department building.

Moorestown is an affluent suburb about 10 miles east of Philadelphia. Republican New Jersey Gov. Chris Christie is scheduled to host his first town hall of the year here on Wednesday at a recreation center less than two miles away.