By Meg Wagner, Veronica Rocha and Brian Ries, CNN
One patient was taken to the University of Maryland Medical Center in Baltimore, Maryland, following the Annapolis shooting, according to Lisa Clough, the director of media relations for the hospital.
No information about patient, including his or her condition, is available at this time.
Clough says she does not know if they are expecting any additional patients.
From CNN's Evan Perez and Shimon Prokupecz
Two law enforcement officials tell CNN that there are multiple injuries as well as fatalities.
A source tells CNN one person, believed to be the shooter, is in custody.
A crime and courts reporter at the Capital Gazette newspaper has tweeted about the shooting, and he said that a gunman "shot through the glass door to the office and opened fire on multiple employees."
"Can't say much more and don't want to declare anyone dead, but it's bad," he said.
He added: "There is nothing more terrifying than hearing multiple people get shot while you're under your desk and then hear the gunman reload."
From CNN's Evan Perez
A law enforcement source told CNN the shooting happened in the newsroom.
Earlier, an officer on the scene would not confirm if the newspaper office building was involved, however, the address police gave matches the one listed on the Capital Gazette's website.
Maryland Gov. Larry Hogan just tweeted about a shooting at the Capital Gazette building in Annapolis. He warned people to stay away from the scene of the shooting.
Hogan said that he was "absolutely devastated to learn of this tragedy in Annapolis."
From CNN's Evan Perez
A law enforcement official tells CNN that one person is in custody, believed to be a shooter at the Gazette building. The source said there are multiple wounded.
Anne Arundel police tweeted that they are continuing to search the building.
From CNN's Noah Gray
President Trump has been briefed on the shooting in Annapolis, deputy press secretary Lindsay Walters told reporters.
The President was in Wisconsin today for meetings with supporters and the groundbreaking ceremony of a new Foxconn plant.
Lt. Ryan Frashure, a spokesperson for the Anne Arundel County Police Department, told CNN affiliate WJLA that officers could not confirm whether any arrests have been made in the shooting.
"We're doing the best we can," he said. "We're doing everything we can to get people out safe and we're trying to minimize the casualties."
Frashure said the shooting occurred at 888 Bestgate Road. Officers, he said, were evacuating the building to "make sure people are out safe."
"And again, there's a lot of factors that got into this. so there's a lot of secondary things we have to look into also," Frashure said. "Whether there's any type -- whether there is other shooters, there might be more than one, bombs, anything like that, so there's a variety of things we have to go through."
He added that officers were focused on getting people out of the building, so they can be reunited with family.
The Anne Arundel Police Department confirmed on Twitter that officers are responding to an active shooter in Annapolis.
An officer on the scene would not confirm if the newspaper office building is involved, however the address matches the one listed on the Capital Gazette's website.