Leaders across the US are sounding the alarm on white supremacist violence in wake of Sat.'s shooting in Jacksonville, FL.

What happened? A white gunman on Sat. opened fire on a store in Jacksonville, killing three before dying by suicide. (Vox)

Jacksonville Sheriff T.K. Waters told reporters Sat. that the gunman penned a racist manifesto before the attack. (Vox)

Waters also revealed that the gunman was chased away by a security guard at Edward Waters University before Sat.'s attack.

Founded in 1866 to educate formerly enslaved people, EWU is Florida's first HBCU. All three victims were Black. (NBC)

Pres. Joe Biden addressed the shooting during a roundtable discussion with civil rights leaders Mon..

Biden: "[Hate] isn't diminishing. [...] There's a whole group of extreme people trying to erase history."

VP Kamala Harris also spoke out Mon.: "There are those who are intentionally trying to divide us as a nation."

Harris: "I believe each of us has a duty to not allow factions to sever our unity."

Several state and local leaders also decried white supremacist violence at a vigil held for the victims on Sun..

Councilwoman Ju'Coby Pittman: "We cannot have someone come from another county, and shoot up this community."

Jacksonville Mayor Donna Deegan: "We have to do everything that we can in this community to bring unity to our city."

Florida Gov. Ron DeSantis was booed as he stepped up to speak at Sun.'s vigil.

DeSantis announced Sun. that the state would set aside $1M+ for EWU to increase security on campus.

Waters also spoke at Sun.'s vigil: "One evil man [...] cannot shake our resolve."

Waters: "I care about every member of this community. [...] This is not who Jacksonville, Florida is."