Police identified the suspect as Steven Nelson Lopez, according to Paul Miles of NewsRadio 840 WHAS.
Lopez, who was charged with attempted murder, is hospitalized with a gunshot wound to his leg, Miles reported.
Reports of shots fired at Jefferson Square Park came in about 9 p.m., Louisville Metro police said in a statement, followed by calls that the Jefferson County Sheriff’s Department was performing life-saving measures on Gerth, who died at the scene. Shortly after, police were told of a shooting victim across the street at the Hall of Justice.
Video posted on social media appeared to show a man opening fire into the park as people scrambled for cover. The footage later showed at least one person bleeding profusely on the ground.
Officers cleared the park and police “are trying to gather as much information as possible in order to identify all who were involved in the incident,” according to a statement. No information about arrests and possible suspects was immediately released.
“I am deeply saddened by the violence that erupted in Jefferson Square Park tonight, where those who have been voicing their concerns have been gathered,” Louisville Mayor Greg Fischer said in a statement. “It is a tragedy that this area of peaceful protest is now a crime scene.”
The park has for weeks been the epicenter for protests in the city after the police killings of Taylor and George Floyd. The Saturday night shooting was at least the second during nearly a month of protests in Louisville over Taylor's death. Seven people were wounded May 28 when gunfire erupted near City Hall, prompting a statement from Taylor's mother asking people to demand justice "without hurting each other."
"Praying for our city," tweeted Kentucky state Rep. Charles Booker of Louisville late Saturday. The Democrat is running for his party's nomination to challenge Republican Senate leader Mitch McConnell in the fall.
Taylor, a 26-year-old Black woman, was killed in her Louisville home in March by police who were serving a no-knock warrant. Protesters have been calling for the officers involved in her death to be charged. One of the officers was recently fired.
Kenneth Walker, Taylor’s boyfriend, was originally charged with attempted murder after he fired a shot at one of the officers who came into the home. Walker has said he thought he was defending from an intruder.
The no-knock search warrant that allows police to enter without first announcing their presence was recently banned by Louisville's Metro Council.