VIRGINIA BEACH, Va. (WAVY) — City offices will reopen Tuesday at the Virginia Beach Municipal Center four days after 12 people were killed in a mass shooting.

Offices at the center were closed Monday as employees, residents and family members continued to mourn the 11 city workers and contractor who were killed in the shooting.

Workers who returned to work Tuesday were seen greeting each other with hugs outside Virginia Beach City Hall.

The 11 employees killed in the shooting included engineers who worked to maintain streets and protect wetlands and three right-of-way agents who reviewed property lines. They were also an an account clerk, a technician, an administrative assistant and a special projects coordinator.

Between them, these 11 people served the city for more than 150 years.

The twelve people killed were identified as Tara Welch Gallagher, Mary Louise Gayle, Alexander Mikhail Gusev, Katherine A. Nixon, Ryan Keith Cox, Joshua O. Hardy, Michelle “Missy” Langer and Herbert “Bert” Snelling, all of Virginia Beach; Laquita C. Brown and Robert “Bobby” Williams, both of Chesapeake; Richard H. Nettleton of Norfolk.

City manager Dave Hansen said in a news conference Sunday Building 2 — where the shooting happened — will be “closed until further notice.” City leaders are planning to move the operations from the building throughout this week and next week.

Access to Building 2 is still blocked off at the complex as the FBI and Virginia State Police investigate the shooting.

The suspect in the shooting, 40-year-old DeWayne Craddock, worked in Build 2 as an engineer in Virginia Beach’s utilities department. Craddock sent a resignation email to his supervisor the morning of the shooting.

“I want to officially put in my two weeks’ notice to vacate my position of Engineer III with the city of Virginia Beach. It has been a pleasure to serve the city, but due to personal reasons I must relieve my position,” Craddock wrote in the email, which authorities cleared for release on Monday.

Police Chief Jim Cervera said investigators are retracing the gunman’s activities on the day of the attack, using his electronic keycard. They are also reviewing his personal and professional lives trying to find a motive.

City officials have maintained the suspect was in good standing in his position, and was not in the process of being terminated. A source at city hall said Craddock was told a couple of weeks before the Friday tragedy that he was doing a good job.

The gunman was killed following an exchange of gunfire with police.