Authorities in Alabama are now offering a combined $100,000 reward Monday for information surrounding a mass shooting in Birmingham over the weekend that left four dead and at least 17 others injured.

Birmingham Mayor Randall Woodfin said the primary objective now is to "hunt down, capture, arrest and convict the people who are responsible" for the violence that erupted Saturday night outside a popular nightspot in the city’s Five Points South district. As of Monday, no suspects have been arrested.

"As a community we cannot give safe harbor or shelter to people who want to just simply kill people. We can’t give them cover. They should not feel safe in our community. They should not feel safe anywhere," Woodfin said during a news conference, urging the public to come forward with information. "It’s your time to step up, and we need you."

"You see, it’s easy to see people in a line who are most likely unarmed, because to enter a club you can’t have a weapon on you. And so, on one hand, as heinous as this was, it was also one of the most cowardly things we have also seen. They’re cowards," Woodfin continued.

WHITE HOUSE CONDEMNS ALABAMA SHOOTING THAT POLICE SAY KILLED 4, WOUNDED 17 IN ALLEGED PAID ‘HIT’

"Everyone who wants to play detective on social media, everyone in the streets that's pointing the finger at police and everyone else, this is your time to step up. And there is an ample reward for you doing your part as a community member," he also said.

The combined reward is being offered by the FBI and Crime Stoppers of Metro Alabama.

Police Chief Scott Thurmond said at the news conference that police are still sifting through tips and that five of the injured victims remain hospitalized.

The shooting occurred on the sidewalk and street outside Hush Lounge, where blood stains were still visible on the sidewalk Sunday morning, according to The Associated Press.

MASS SHOOTING LEAVES 4 DEAD IN BIRMINGHAM, ALABAMA

Thurmond previously said authorities believe the shooting targeted one of the people who was killed, possibly in a murder-for-hire. A vehicle pulled up and "multiple shooters" got out and began firing, then fled, he said.

"Some of the individuals that were killed have extensive criminal histories," Thurmond also told reporters on Monday. "And because of that, there’s often times motivation from others and there’s people who are willing to pay to have them killed. And so that’s part of it."

Police said about 100 shell casings were recovered. Thurmond said law enforcement was working to determine what weapons were used, but that they believe some of the gunfire was "fully automatic." Investigators also were trying to determine whether anyone fired back, creating crossfire.

Officers found two men and a woman on a sidewalk with gunshot wounds, and they were pronounced dead at the scene. An additional male gunshot victim was pronounced dead at a hospital, according to police.

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Police identified the three victims found on the sidewalk as Anitra Holloman, 21, of the Birmingham suburb of Bessemer, Tahj Booker, 27, of Birmingham, and Carlos McCain, 27, of Birmingham. The fourth victim has yet to be identified to the public.