At least 4 dead and several injured in shooting in popular entertainment district in Birmingham, Alabama, police said

At least four people were killed and dozens more injured in a mass shooting in one of Birmingham, Alabama's most popular entertainment districts on Saturday night, Birmingham police said.

Shortly after 11 p.m., “multiple gunmen fired multiple shots at a group of people” in the Five Points South area, Birmingham police Officer Truman Fitzgerald said.

When officers arrived at the scene, they found two unconscious men and a woman with gunshot wounds. All three were later pronounced dead at the scene, Fitzgerald said. A fourth victim died at a nearby hospital, he added.

As of early Sunday, no suspects were in custody, Fitzgerald said.

The victims were all outdoors on the sidewalk or in the street, Fitzgerald said. Investigators are trying to determine whether the shooters walked toward the victims or drove past in a vehicle, he added.

Additional gunshot victims were identified in the area and additional victims were taken to local hospitals, Fitzgerald said. The University of Alabama at Birmingham Hospital admitted 11 of the victims, including one of the deceased, Hannah Echols, a hospital spokeswoman told CNN. The victims' conditions were not disclosed.

“We have dozens of gunshot victims from this area,” Fitzgerald said. “I'm told at least four of those gunshot victims are critically ill, the others have various injuries.”

It is unclear exactly how many people opened fire or what motivated the violence. Fitzgerald said police are investigating whether there were “multiple shots.”

According to Fitzgerald, several law enforcement agencies are assisting with the investigation. Birmingham police have asked businesses in the area to provide them with any surveillance footage and have asked the public to contact them with any relevant information.

“Rest assured, we will do everything in our power to ensure that we uncover, identify and bring to justice those responsible for the attacks on our people,” he said.

Five Points South is a bustling neighborhood known for its restaurants, nightclubs, pubs, and live music venues. It is located near the campus of the University of Alabama at Birmingham and is just a short drive from downtown Birmingham.

Fitzgerald said the mass shootings had “more to do with culture than crime,” adding: “We see far too many conflicts decided by bullets.”

The Alabama incident joins a list of at least 403 mass shootings in the U.S. this year, according to the Gun Violence Archive. The archive, like CNN, defines a mass shooting as one in which at least four people are shot, not including the shooter.

This is a developing story and will be updated.

CNN's Aaron Eggleston contributed to this report.

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