This TV video frame grab courtesy of WDBJ7-TV in Roanoke, Virginia shows two WDBJ7 employees killed in an attack at Bridgewater Plaza in Moneta, Virginia on August 26, 2015.[Photo/CFP]

The suspected gunman in the shooting deaths of two television journalists in Virginia on Wednesday was a veteran anchorman with a history of workplace grievances who had previously sued a Florida station alleging discrimination because he was black.

While authorities said they had not determined a motive, perceived racism appeared to be a factor in the shootings, according to recent postings the suspect is believed to have made on social media and a fax that ABC News said the suspect sent.

Vester Flanagan, 41, who went on the air under the name Bryce Williams, was a former employee of WDBJ7 in Virginia, where both of the slain journalists worked. The journalists, who were both white, were killed during a live television broadcast earlier this morning.

Posts on a Twitter feed by a man identifying himself as Bryce Williams, Flanagan's on-air name, accused one of the victims of "racist comments," and noted that a complaint had been filed with a government agency that enforces discrimination claims.

In a 23-page fax ABC News said was sent two hours after the shooting, he cited as his tipping point the racially motivated shooting that killed nine black churchgoers in Charleston, South Carolina, earlier this summer.

Saying he had suffered racial discrimination, sexual harassment and bullying at work, Flanagan described himself as "a human powder keg," the network said.

Flanagan aired similar grievances in a 2000 lawsuit filed in U.S. federal court against a Florida station, WTWC-TV in Tallahassee. In that suit, he said a producer had called him a "monkey," and he accused a supervisor of calling black people lazy for not taking advantage of college scholarship opportunities.

The Florida case was settled and dismissed the next year, court records show.