The gunman who went on a shooting rampage in a Maryland newsroom, killing five people and leaving others seriously injured overnight, has been identified.
Law enforcement sources have named the killer as Jarrod Ramos, who has previously sued the newspaper for defamation, according to local media sources.
Officials also released the names of the five people killed in the shooting at the Capital Gazette.
Lt. Ryan Frashure of Anne Arundel County Police read the names at a news conference Thursday night (US time), hours after the shooting at the newspaper.
They are: Wendi Winters, John McNamara, Gerald Fischman, Rebecca Smith, and Rob Hiaasen.
Winters was the special publications editor. McNamara was a writer. Fischman was editorial page editor. Smith was a sales assistant. Hiassen was an assistant editor and columnist.
NBC News reported Ramos had a history with the paper, filing a defamation suit against it in 2012.
A US official said Ramos was identified using facial recognition technology after he damaged his fingerprints in what police believe was an attempt to prevent rapid identification.
Police say the Capital Gazette newspaper had received threats on social media before today's deadly shooting.
County acting police chief William Krampf said investigators were trying to determine whether the "general" threats were connected to the suspect.
Krampf said a white male in his 30s used smoke grenades when he went into the building.
Journalists at the Capital Gazette covered the mass shooting that unfolded in their office - and continued working to put out a Friday paper.
Photojournalist Joshua McKerrow tweeted Thursday that he wasn't in the office when five of his colleagues were killed, but he headed to the scene.
McKerrow says he is working to cover the story with two Capital Gazette reporters and with assistance from colleagues at the Baltimore Sun, which is owned by the same company.
Reporter Chase Cook tweeted: "I can tell you this: We are putting out a damn paper tomorrow."
High school sports editor Bob Hough told the Associated Press he and a colleague were working on the sports section from his home. Hough, who wasn't at the office during the shooting, says he expects to publish a full section.
Journalists at the historic Maryland newspaper took to social media to seek help and inform others what was happening during a gunman's deadly attack.
News of the massacre began with a chilling tweet including the paper's address sent by a summer intern: "Active shooter 888 Bestgate please help us."
Police reporter Phil Davis said he could hear people getting shot as he took cover.
"There is nothing more terrifying than hearing multiple people get shot while you're under your desk and then hear the gunman reload," he tweeted.
Meanwhile, a GoFundMe account set up for the newspaper has raised more than US$20,000 within just three hours.
The account was set up by a fellow journalist, Bloomberg government reporter Madi Alexander. It urged people to give what they can to help the newspaper's journalists pay for medical bills, funeral costs, newsroom repairs and other expenses.