A man kneels near a memorial outside of the offices of WDBJ7 in Roanoke, Virginia August 26, 2015. [Photo/Agencies]

One of his former Florida colleagues remembered Flanagan as "quirky," but said he never displayed behavior suggesting he would be capable of such a violent crime.

"He had his idiosyncrasies, a little quirky sometimes," said Michael Walker, the weekend producer at the Tallahassee station when Flanagan was working as a weekend anchor. "It probably wasn't any different than any other on-air personality."

Walker, who is also black, noted that he had not experienced discrimination at the station.

Flanagan, who accused the station of terminating his contract because he had filed a report of racism with a state agency, said in the lawsuit he suffered emotional distress and financial losses as a result of his treatment at the station.

The NBC affiliate, which stopped broadcasting newscasts in late 2000, said at the time of the lawsuit that his contract was not renewed due to "corporate belt-tightening," according to an article in the Tallahassee Democrat at that time.

Representatives from the station could not immediately be reached for comment.

Flanagan's 20-year career in journalism included stints at local news stations in San Francisco; Savannah, Georgia; and Midland, Texas, according to his LinkedIn profile. It said he also worked briefly outside of journalism as a customer service representative.

He graduated from San Francisco State University in 1995 with a degree in radio and television, the school confirmed.

According to a Facebook page believed to belong to the suspect, he was originally from Oakland, California, but most recently living in Roanoke, Virginia, where WDBJ7 broadcasts.

There, he gained a reputation as someone who was difficult to work with because of his anger, station manager Jeff Marks said during a live broadcast.

"Vester was an unhappy man," Marks said, adding that he had to be escorted out of the building by police after he was terminated from the station in 2013.

"He did not take that well," he added.