LOUISVILLE (WHAS11) – The Louisville Metro Police Department says the homicide near the Big Four Bridge on Sunday night was not a random act.

LMPD Chief Steve Conrad says the homicide was gang related. LMPD’s Emily McKinely could not detail exactly how the incident was related to gang activity.

LMPD says what happened near the Big Four Bridge on Sunday night stemmed from an impromptu pool party at 4th and Brandies. A crowd of people, police said that crowd consisted of more than 500, had spilled out from the party and into the roadway. The crowd impacted traffic and businesses.

LMPD’s fourth division was contacted by University of Louisville Police saying they needed assistance in handling the crowd. By 6 to 6:30 p.m. the crowd had dispersed by police officers.

The crowd eventually moved to Waterfront Park. The Real Time Crime Center was asked to monitor the area through the cameras posted in the area. The fourth division had put the First Division on alert concerning the crowd possibly heading toward the Big Four Bridge.

At around 6:45 p.m. the First Division asked for help in handling the crowd at Big Four Bridge.

LMPD says it was at 7 p.m. the bridge was shut down. It was closed until 9 p.m. The crowd was gathered at the base and at least 30 officers eventually responded to the scene.

From 7 to 9:15 p.m. small scuffles were occurring but officers were addressing them as they happened, police said.

That crowd had dispersed from Waterfront Park by 9 p.m.

That is when gunshots were heard, according to police.

Police said a foot chase began. The subject, James Porter, disregarded police commands and he was armed with a gun. According to the police report, Porter had gotten into a physical altercation with an unknown male. Porter was arrested at Waterfront Park.

At 10:07 p.m. more gunshots were heard. A car was observed fleeing the scene a gun was tossed from the window of the vehicle and LMPD says everyone was detained and arrested in this incident.

At this time three shooting victims had been located west of the bridge. It was later, at 10:30 p.m., a fourth shooting victim showed up at University Hospital. That person had non-life threatening injuries. One shooting victim, identified as 22-year-old Anton Brown, later died at the hospital.

LMPD stressed, in their Monday afternoon news conference, they do not know how the arrests are related to the homicide or other shooting victims. No one has been charged in the homicide.

Lt. Emily Mckinley said they are still in the early stages of their investigation.

LMPD’s Conrad and Emily McKinley said they need the community’s help in closing their investigation.

"We cannot effectively do our jobs without the community's support and help," Conrad said.

“We need your help. ...Until we get some information to put all this together, we cannot make arrests,” McKinely said.

If you have any information on Sunday night's homicide call police at their anonymous tip line 574-LMPD.