Three people were killed and two others were seriously injured in a shooting early Sunday at a crowded Wisconsin bar, prompting a two-state search for at least one gunman who authorities said targeted the victims.

Gunfire broke out inside and outside the Somers House Tavern in Kenosha, Wisconsin, around 12:42 a.m. when a man who had been kicked out of the bar returned with a handgun and opened fire, Kenosha County Sheriff David Beth said at a news conference Sunday morning.

“We don’t believe this was a random act,” Beth said. “From what I’ve been told, the three people who passed away probably knew each other. This was a targeted situation.”

Beth said it was not immediately clear why the gunman was asked the leave the tavern.

“This person that was asked to leave wasn’t cooperating with the management there,” Beth said. “But I believe he returned a short time later and came in and did the shootings.”

Beth did not rule out the possibility that more than one gunman was involved in the fatal shooting, saying more than one gun could have been used.

He said detectives are combing through surveillance video and interviewing witnesses in an attempt to identify the suspect or suspects. Law enforcement agencies throughout southeast Wisconsin and northern Illinois were searching for the suspect, the sheriff said.

In a statement sent out earlier Sunday, Sgt. David Wright of the sheriff’s office described the suspect as “a Black male over six feet tall wearing a light-colored hooded sweatshirt.”

Beth said he could not immediately say if any of the three people killed worked at the Somers House or were patrons. The names of the victims have not been released.

“I believe the gunman knew who the victims were. Whether the victim knew the gunman, I don’t know,” Beth said.

He said investigators believe a second shooting that occurred outside the bar is related to the bloodshed inside.

Beth said one of the people shot managed to jump in a car with two other people, who flagged down a law enforcement officer. He said the officer moved the victim to his patrol car, but the person died en route to a hospital.

The shooting caused a lockdown at nearby Carthage College, but Beth said there was no threat to the surrounding community.

He asked the public to contact the sheriff’s office if they witnessed the shooting or have information to help investigators identify the killer.

ABC News’ Ahmad Hemingway contributed to this report.