From the moment details began emerging about Vester Lee Flanagan II, the ex-TV reporter and gunman who killed two of his former colleagues at WDBJ-TV in Moneta, Virginia, Wednesday while they were live on the air, opponents of Black Lives Matter said they wanted its supporters to reject Flanagan’s claims of racial discrimination as his motivation. Attempts to link Flanagan to the social justice movement by some social media users, including acquitted Trayvon Martin killer George Zimmerman, sparked a feud on social media that went viral Thursday.

The hashtag “#BlackLivesMatter” was trending in part because Flanagan, 41, had described several episodes of mistreatment by his former employer in a lengthy suicide note he sent to another news station near Roanoke, Virginia. The note contained allegations that he suffered harassment, bullying and discrimination for being black and gay, according to a New York Times report.

In the note, Flanagan, who had previously sued WDBJ and another former broadcast news employer, wrote of a desire to spark a race war, a similar sentiment similar to that expressed by Dylann Roof, the accused gunman in the Charleston, South Carolina, church shooting in June that intentionally targeted black parishioners. Flanagan reportedly said the Charleston shooting is what pushed him over the edge.

Flanagan's three victims, who were white, included two WDBJ employees, Alison Parker and Adam Ward, who died after he opened fire on them, and a third woman, Vicki Gardner, who sustained critical injuries before having her condition upgraded to good. The Twitter discussion between supporters and opponents of Black Lives Matters centered on attempts to affirm that “all lives matter” and change the movement to one that appeared less racially exclusive.

To be clear, I did not "assume" that the shooter was white yesterday. Initial reports said he was white. pic.twitter.com/NmwqE2gmuT — deray mckesson (@deray) August 27, 2015

If the idea of #BlackLivesMatter bothers u, ask yourself: Why?! The irritation over elevating blackness to equal status reveals something... — Charles M. Blow (@CharlesMBlow) August 26, 2015

Anyone who treats #BlackLivesMatter as a legitimate "movement" after today's display should be ashamed. pic.twitter.com/6hzVTHTyqk — Joe Prich (@JoePrich) August 26, 2015

Zimmerman, the man who in 2012 fatally shot the unarmed black teen Martin in Sanford, Florida, drew considerable backlash on Twitter for tweets that many called inappropriate and inconsiderate in a time of tragedy. Among several incendiary posts, Zimmerman argued that Black Lives Matter activists would not speak out and condemn the murders of Parker and Ward. He also criticized President Barack Obama for not issuing a statement about the shooting, after having famously spoken out about Martin’s death.