A gunman killed multiple people at the Capital Gazette newsroom in Annapolis, Maryland, according to The Baltimore Sun.
At least five people are confirmed dead, according to authorities on the scene.
An unconfirmed number of people are injured, according to numerous reports. The suspect has been taken into custody, Anne Arundel County Sheriff Ron Bateman confirmed.
The Bureau of Alcohol, Tobacco, Firearms and Explosives responded to the “shooting incident” at the Gazette, The Sun reported.
It's unclear how many people were inside the building when the killer stormed the newspaper offices.
Phil Davis, a courts and crime reporter at The Gazette, was inside the building during the attack. He sent out a series of tweets about the shooting.
Acting Police Chief William Krampf said during a news conference that police arrived within 60 seconds after receiving the first 911 call.
One official said the suspect was a male in his 20s and had no identification on him.
According to CBS News, the suspect is not cooperating with police.
Some of the injured have been transported to nearby hospitals.
This story is evolving and will be updated as information becomes available.