PHOTOS: Mourners pray after 12 killed in Virginia Beach shooting

VIRGINIA BEACH, Va. -- Vigils are taking place across Virginia Beach as the community grapples with the aftermath of Friday's mass shooting a municipal center that left 12 victims and the shooter dead in Virginia's largest city.

A group of people formed a prayer circle outside at the end of Courthouse Drive outside Building 10 in honor of a church member killed before a Saturday morning news conference that formally identified the 12 shooting victims, WTKR reported. 

Another community prayer vigil took place at the Regal Cinemas in Strawbridge Marketplace at 10 a.m. less than 24 hours after the massacre.

The city will host a remembrance ceremony Thursday at 7 p.m. at Rock Church (640 Kempsville Road), officials announced during a Saturday afternoon news conference.

"We encourage anyone who wants to share in that to attend," Virginia Beach Communications Director Julie Hill said.

Additionally, Hill said folks who would like to drop off flowers, candles or other mementoes can do so at the flagpole outside Virginia Beach Police Headquarters (Building 11 -- 2509 Princess Anne Road).

More events are slated Saturday and the coming days as the community begins the long road to healing.

The gatherings come after a Virginia Beach city employee killed 12 people -- including colleagues -- in a shooting rampage in the municipal building where he worked, investigators are scrambling to nail down why it happened, officials said Saturday.

"It's still a sense of shock, disbelief. Why did this happen?" Bobby Dyer, mayor of the coastal Virginia city, told CNN, standing across the street from the multistory brick building where the massacre happened.

"I guess the big question is why. We want to know, too."

Authorities said DeWayne Craddock, 40, a certified professional engineer in the city's public utilities department, moved through and opened fire on three floors of Building 2 of the Virginia Beach Municipal Center at the end of Friday's workday.

Craddock killed a dozen people and injured others, and sent terrified witnesses running out of the building or hiding under desks before the shooter died at the end of a lengthy gunbattle there with four police officers, authorities said.

Eleven of the 12 killed were city employees. The other was a contractor who was there to fill a permit, City Manager Dave Hansen said.

Officials are now left not only answering questions about what happened but also dealing with the deaths of their colleagues. Hansen said he'd worked with many of them for years, and served with one in the US military in Germany. Dyer said the contractor was a friend of his who'd done carpentry work at his home.

"They leave a void that we will never be able to fill," Hansen said Saturday before he read the victims' names.

Four others in the shooting were hospitalized, police said. They had surgery Friday night, and three are in critical condition, while one is in fair condition, hospital officials said. An officer was shot in the gunfight but survived because of his ballistic vest, police Chief James Cervera said.

Friday's massacre is the deadliest in the United States this year and adds the Virginia city to a grim list of places affected by a mass shooting.

Many victims were longtime workers for the city

Hansen said the 11 slain city employees had worked for Virginia Beach for times ranging from 11 months to 41 years.

They were Virginia Beach residents Tara Welch Gallagher, Mary Louise Gayle, Alexander Mikhail Gusev, Katherine A. Nixon, Ryan Keith Cox, Joshua A. Hardy, Michelle "Missy" Langer; Chesapeake residents Laquita C. Brown and Robert "Bobby" Williams; Norfolk resident Richard H. Nettleton; and Powhatan resident Christopher Kelly Rapp.

Also killed was the contractor, Herbert "Bert" Snelling, of Virginia Beach.

Nettleton, an engineer with the city's public utilities department, "served with me as a lieutenant in Germany in the 130th Engineer Brigade," said Hansen, the city manager.

The city government said it will hold a remembrance event for the slain victims at 7 p.m. Thursday at Rock Church in Virginia Beach.

Gunman fired through all floors except the basement, officials say

Officials said Saturday they were either searching for answers, or unwilling to reveal details, about what spurred the shooting.

A Virginia government source briefed on the investigation told CNN the shooter was a "disgruntled employee."

Craddock was a certified professional engineer in the city's public utilities department for about 15 years, officials said. He is listed on department news releases as a point of contact for information on local road projects over the past several years.

Cervera, the police chief, said his investigators still don't know the shooter's motive. He and Hansen declined to answer questions Saturday about whether Craddock had threatened anyone in the building previously or faced discipline at work.

The gunfire started at the end of the workday while people still were visiting the municipal center for business. He fired on every floor except the basement as he moved through the building, officials said

Craddock had a security pass "like all employees had" to access inner offices of the building, beyond the public service desk near the entrance, that aren't otherwise accessible to nonemployees, Hansen said.

Megan Banton told CNN she was on the building's second floor when the shooting started. She and about 20 of her colleagues pushed desks against the doors before rushing to hide in their bosses' office.

She called 911. She said she could hear yelling, screaming and muffled gunshots.

"I was trying to listen to what (was happening) and listen to 911 (operator), and we just hoped it would be over soon," she said.

"It felt like hours."

Officers gave the shooter first aid, chief says

Four officers confronted the shooter inside the building in what the chief called a "long gunbattle."

Two detective supervisors entered the building from their workplace across the street, and were eventually joined by two K-9 officers. The four began a shootout with the suspect, and helped stop him from committing more carnage, Cervera said.

The gunman was wounded, and officers tried to save him, the chief said.

"Even though he was involved in a long-term gunbattle with these officers when he went down, they did what cops do and they rendered first aid to this individual," Cervera said Friday.

The chief said that a .45-caliber pistol, a suppressor and several empty, higher-capacity magazines were found near the shooter.

A rifle also was found at the shooting site, according to a law enforcement official. Cervera has declined to comment about the presence of a rifle.

Investigators have found "additional weapons" at the gunman's home, the chief said.

He was thought to have purchased the firearms legally, according to initial information investigators have, a law enforcement official said.According to Virginia's Department of Professional and Occupational Regulation, Craddock obtained his certified professional engineer license in the state in 2008. The license wasn't set to expire until June 2020.

Depend on WTVR.com and CBS 6 News for complete coverage of this developing story. Check back with WTVR.com and watch CBS 6 News for updates. 

The CNN Wire contributed to this report.

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