Law enforcement sources are reported as naming the shooting suspect as Jarrod Ramos, a man who had a long-running feud against the Capital newspaper.
US media say law enforcement sources confirmed the identity of the shooting suspect as 38-year-old Jarrod Ramos from Laurel, Maryland.
Ramos filed a defamation lawsuit in 2012 against columnist Eric Hartley, the Capital Gazette Communications group and the paper's former editor, Thomas Marquardt.
The case was prompted by a newspaper article from July 2011 that reported on a criminal harassment case against him.
Jarrod Ramos is suspected of fatally shooting five people in the Capital newsroom in Annapolis, Maryland. Source: Anne Arundel Police Department
A Twitter account created in his name, references the defamation suit and outlines his grievances against the newspaper.
The account uses a profile image of Hartley and a banner image with photos of Marquardt and the former owner of the paper, Philip Merrill.
The @EricHartleyFrnd account states in its description: "Dear reader: I created this page to defend myself. Now I'm suing the shit out of half of AA County and making corpses of corrupt careers and corporate entities."
Up until January 2016, the account regularly posted views on Anne Arundel County news and also commented on a deadly shooting at a French newspaper Charlie Hebdo in 2015.
A hiatus on the account ensued until moments before the Capital shooting, when he posted a message that read: f**k you, leave me alone.
A screenshot of Ramos' Twitter account dedicated to voicing his grievances against the newspaper. Source: SBS
The Capital story detailed the lawsuit filed by a woman who claimed Ramos had stalked and harassed her both online and offline for months, including calling her employer in an attempt to get her fired.
Police follow lead of social media threats
Police earlier said they are investigating threats of violence made on social media against the Capital newspaper ahead of a deadly shooting that killed five people.
Social media threats were made against the Annapolis newspaper where five people were shot dead in what police have described as a "targeted" attack.
Police said they have yet to make any final conclusions on the shooting suspect's motivation, who is in police custody and facing questioning.
They described him as a white adult male in his late 30s who was armed with a long gun.
Maryland police officers patrol the site of the shooting. Source: AAP
Suspect had a 'vendetta'
Lieutenant Ryan Frashure of Anne Arundel County Police said it was clear the shooting suspect had a vendetta against the local newspaper.
“This was quite obvious, and quite apparent, that this individual had some type of vendetta against The Capital newspaper, and they specifically targeted (the paper),” he said.
The deputy police chief of Anne Arundel county, Bill Krampf, said investigators were trying to ascertain who sent threats of violence against the media outlet.
The threats were sent over social media earlier in the day before the shooting.
He said the threats had not singled out individual staffers in the newsroom.
“We have no knowledge at all that he was targeting any one specific individual,” he said.
Witnesses questioned
About 170 people are being questioned as witnesses after they were evacuated from the four-storey building, which has 30 tenants, including the newspaper office.
“The building is going to be closed indefinitely until we do what we got to do,” Lieutenant Frashure said.
“Our primary concern is to do what we can do so that we can best prosecute this case.”
He urged the media to have patience and rely on only official spokespersons on the police investigation.
“There are a lot of moving parts here and you know our detectives are doing their best. They'll get to the bottom of it and find out exactly [what happened].”
Deputy police chief Krampf refused to confirm earlier media reports on the identification of the suspect using facial recognition technology, after his damaged fingerprints thwarted efforts to use thumb print identification.
He fielded repeated questions from reporters on the information from an unnamed source close to the investigation, cited by AP news agency.
"I'm gonna be really clear about this," he said. "We have no information about facial recognition or anything about his fingerprints. If I had that information, I would give it to you."
