Many questions remain in the wake of Friday’s shooting at a municipal building in Virginia Beach, Virginia that left 13 dead, including the shooter.

Just a few hours after emailing a resignation letter to city management Dwayne Craddock, 40, a city engineer, entered the office building where he worked and fired indiscriminately on workers, many of whom he had worked with for years.

Craddock shot one person in a car before entered the building, where he fired at victims on three floors, according to Virginia Beach Police. He was fatally wounded in a lengthy shootout with police.

The victims included 11 Virginia Beach public works employees and one contractor. Four victims remained in critical condition as of Sunday morning, Sentara Virginia Beach General Hospital said in a statement. The shooting spree was among the deadliest episodes of workplace violence in the United States in recent years.

Authorities have yet to determine a motive for the bloody massacre. Virginia Beach City Manager Dave Hansen reported that Craddock was not forced to resign and that Craddock’s “performance was satisfactory.” The city manager said the alleged gunman was “within good standing in his department” and had “no issues of discipline ongoing.”

On Sunday, however, Hansen revealed that Craddock had put in his resignation, emailing his two-week notice just hours before the shooting took place. Hansen and Virginia Beach Police Chief James Cervera insisted that the gunman had not been terminated or forced out and had left his job voluntarily. Investigators were reportedly still trying to recover a copy of the email.

“We have an open investigation just in its third day. This includes establishing a motive,” Hansen said. “Whether employment status has had anything to do with these events? That will be part of the ongoing investigation.”

The New York Times on Saturday reported that a person close to Virginia Beach’s city government, who was not authorized to speak publicly, said that Craddock had no history of behavioral problems until recently, when he began acting strangely and getting into “scuffles” with co-workers.

“The person said that tensions had escalated in the past week, adding that the man had gotten into a violent altercation on city grounds and was told that disciplinary action would be taken,” the Times reports. This story has not been corroborated by city officials.

Co-workers and neighbors described nothing out of the ordinary in Craddock’s behavior prior to the shooting rampage. Co-worker Joseph Scott told CNN that he had worked with Craddock for several years and that he used to be “what I thought was a good person.” Another who did not want to be named said the gunman was “a nice guy” and “not a monster.”

Scott said he had seen Craddock earlier on Friday brushing his teeth in the bathroom as he usually did after lunch, and that Craddock had wished him a good weekend. Later that day, Scott survived the shooting by barricading himself in an office with others. When they were able to leave the building, they had to step over the bodies of co-workers who had been gunned down.

While Craddock was not known to co-workers and acquaintances as a violent man, he appeared to have methodically planned the attack. When 40 members of police and FBI agents searched through Building No. 2, the scene of the shootings, to collect evidence they found two 45-caliber pistols at the scene. Both had been legally purchased, one in 2016 and the other in 2018, and were not known to have been involved in any earlier crimes. Investigators found two more legally purchased firearms in Craddock’s home.

One of the pistols used in the shootings had a suppressor, or silencer, and several empty extended magazines were found at the scene. Not only had Craddock come heavily armed, but it is likely that he used the suppressor in an effort to confuse occupants of the building as to where the shots were coming from. Some employees reported that the shooting sounded further away than it actually was, while another said the shots sounded like a nail gun.

Craddock had worked as a certified professional engineer in the city’s public utilities department for about 15 years. He had a Bachelor of Science degree in civil engineering. He enlisted in the Virginia National Guard in 1996 and was assigned to the First Battalion, 111th Field Artillery Regiment in Norfolk, Virginia as a cannon crew member, gaining the rank of specialist. He was discharged in 2002 for reasons not disclosed by the Guard.

While it cannot be determined at this point whether Craddock’s time in the National Guard had any role in shaping the behavior that would ultimately lead to his murderous outburst, the military plays a large role in the economy and culture of Virginia Beach. The city is part of the Hampton Roads metropolitan area in Southeastern Virginia/Northeastern North Carolina, bordering the Atlantic Ocean. Hampton Roads is known for its large military presence and is home to about 20 military facilities.

Virginia Beach—the largest city in the state with about 450,000 residents—is known as resort city with miles of beaches and hundreds of hotels, motels and restaurants along its shore. But while tourism plays a major role in the city’s economy, several US military bases are located there, including the US Navy’s NAS Oceana and Training Support Center Hampton Roads, and the Joint Expeditionary Base East, located at Cape Henry. NAS Oceana is the largest employer in Virginia Beach.

The city is also the headquarters of the Christian Broadcasting Network (CBN), the conservative evangelical Christian religious television network founded by televangelist Pat Robertson. CBN was founded in 1960 in nearby Portsmouth by Robertson, who had recently become a born-again Christian.

While the news media describe Friday’s events in Virginia Beach as yet another unexplainable “senseless killing,” there is no effort to look to the deeper social causes that might propel a seemingly ordinary person to gun down his co-workers with methodical brutality. The Democratic Party offers only its repeated calls for gun control.

There is no consideration given to the impact of the military presence in Virginia Beach and the culture of war and imperialist violence propagated by both big business parties. The Christian right’s assault on democratic and reproductive rights and its dissemination of reactionary and anti-scientific views are also dismissed. The role played by these forces in molding the psyche and actions of Craddock may emerge in future days.