At least 12 people have been killed and four injured in a mass shooting at a Virginia Beach Municipal Building Friday, according to authorities.
Police Chief James Cervera said Friday at a press conference that the shooter entered Building 2 of the centre shortly after 4 p.m. and opened fire “indiscriminately” at workers, going from floor to floor.
He said the shooter was a “disgruntled” longtime employee of the city’s Public Works Department.
At least four police officers engaged the suspect in a “long-term gun battle,” according to Cervera. Police administered first aid on him at the scene and he later died either en route or at the hospital.
He said the suspect was armed with a .45-caliber handgun with a suppressor and extended magazines.
WATCH: ‘We were all just terrified’: Worker describes terror as shooter opens fire killing 12, injuring several others
Victims were found on three floors and one victim was shot in a car outside the building, according to Cervera.
Police earlier said they believe the suspect was acting alone. His name has not been released yet because police are still notifying his family, Cervera said.
Eleven victims were initially reported by police but an additional one was announced at a later news conference by Cervera. He said the latest victim succumbed to injuries on the way to the hospital.
WATCH: 12 dead, 9 injured in municipal building shooting in Virginia Beach
At least four people have been hospitalized, according to Cervera, and are undergoing surgery.
WATCH: 12 dead, several injured in shooting at Virginia Beach: police
Cervera said police are in the process of identifying victims so families can be notified.
Megan Banton was at the scene at the time of the shooting.
She said she hid in her supervisor’s office with around 20 others as they could hear gunshots outside, and tried to barricade the door as best they could.
“We tried to do everything we could to keep everybody safe,” she said. “We were all just terrified. It felt like it wasn’t real, that we were in a dream. You are just terrified because all you can hear is the gunshots.”
WATCH: 12 dead, several injured in shooting at municipal building in Virginia Beach
Survivors of the shooting afterward reunited with friends and relatives at a nearby middle school.
Virginia Beach is Virginia’s largest city with a population of less than half a million and is located in the southeast of the state by the Atlantic Ocean. It is a popular vacation spot.
The building where the shooting took place is a suburban complex kilometres away from the beach and downtown business area.
WATCH: ‘A horrific day’ – Virginia governor pledges support after shooting kills 12, injures 9
The White House said in a statement that U.S. President Donald Trump had been briefed on the shooting and “continues to monitor the situation.”
Virginia Beach Mayor Bobby Dyer was visibly shaken at the press conference.
“This is the most devastating day in the history of Virginia Beach,” Dyer said at the press conference. “The people involved are our friends, coworkers, neighbours, colleagues.”
WATCH: Virginia Beach Police engaged in ‘long gun battle’ with shooting suspect
Virginia Governor Ralph Norham responded to the event on Twitter, saying it is a “tragic day” for the community.
“My heart breaks for the victims of this devastating shooting, their families, and all who loved them,” he said, mentioning he is on his way to Virginia Beach.
Virginia Senator Tim Kaine tweeted that he is “devastated” to learn of the shooting and that he will “keep pushing for Congress to take action to prevent the daily scourge of gun violence in America.”
Toronto Mayor John Tory responded as well on Twitter, saying he is “saddened by the news of the senseless tragedy.”
WATCH: Virginia Beach officer saved by bullet proof vest during shootout with suspect: Chief
The shooting happened three months after another mass shooting at a workplace in the U.S., when in February an employee at a manufacturing company in Aurora, Ill., near Chicago, killed five workers and wounded five police officers before he was fatally shot.
-With files from The Associated Press and Reuters