At least five people were killed and several others critically injured after a lone gunman blasted his way into Capital Gazette in Annapolis, Maryland, on Thursday afternoon, Anne Arundel County police said.
The shooter has been arrested, police said without naming the suspect or giving details about the incident.
Baltimore Sun, which owns the Gazette, said Phil Davis, a Gazette crime reporter, wrote on Twitter that a gunman shot through the glass door to the office and opened fire on multiple employees. Davis said he does not want to talk about anyone dead or injured adding that the situation was bad.
The reporter said he was hiding under the desk along with some staff when the gunman suddenly stopped firing. Then the police arrived and arrested the shooter.
Annapolis Mayor Gavin Buckley said quick response by the county police averted more deaths.
TV news channels showed Gazette employees leaving the building with their hands up through a parking lot as officers entered the building to search for the shooter.
Police urged locals to alert them if they see any suspicious person or object.
Maryland Governor Larry Hogan wrote on Twitter he was devastated to learn of the tragedy in Annapolis.
He said he was in contact with County Executive Steve Schuh, and that Maryland State Police were on the scene assisting the county police.
He asked locals to stay away from the area and said he was praying for those at the scene.
A White House spokeswoman said President Donald Trump was briefed on the shooting.
Police visited The Baltimore Sun newsroom too as a precaution.