They brought raffle tickets to a gunfight.

Four members of the Grim Guardians motorcycle club showed up to Twin Peaks restaurant in Waco, Texas, on May 17, 2015, for a meeting about state politics, they claim. Instead, rival motorcycle gangs opened fire on each other before police moved in.

They walked into gunfire, and they left in handcuffs.

When the smoke cleared, nine men were dead, 20 people were injured, and 177 bikers were arrested for engaging in organized criminal activity—including the Grim Guardians.

Now Jim Albert Harris, Bonar Crump Jr., Drew King, and Juan Carlos Garcia are suing the city, law enforcement, and the restaurant for violating their civil rights, slandering their reputations, and more.

They’re not the first bikers to sue over the shootout, but they are the first to demand $1 billion and compare the violence to poison gas attacks in Syria.

It is the “worst police operation initiated by law enforcement in the history of Texas, including the fiasco of the Branch Davidian storming that killed dozens of innocent women and children outside of Waco over 20 years ago (which resulted in far more civilian casualties than the recent gas attacks by Assad of Syria),” said Beaumont attorney Brent Coon, in a press release.

Eventually, Coon claims, Waco’s handling of the shooting “will be shown to be one of the biggest blunders and cover-ups by any law enforcement agency in the country,” and the city will eventually be proven as “another Salem, Massachusetts in a witch hunt for bikers.”

When Harris, Crump, King, and Garcia arrived that muggy day, late Sunday morning, the strip mall was quiet except for the roaring of motorcycles approaching the Hooters-like restaurant from the interstate.

They didn’t know that several Waco law enforcement officials were outside and anticipating violence. Officers established a perimeter around the brawl ahead of time—based on intelligence about the escalating conflict between the Bandidos and Cossacks—and were watching for the fight to break out.

More than 60 Cossacks and allied bikers were already sitting on the patio when the Bandidos arrived. They fought each other in the parking lot with handguns, baseball bats, knives, and brass knuckles.

Around this time, the Grim Guardians rode up.

“They took cover behind a vehicle with a female law enforcement officer,” their lawsuit claims. Crump became separated from the others, but the officer “quickly determined” they were not a threat. She disappeared into the melee after she was ordered to advance, the suit claims.

“In 34 years of law enforcement, this is the most violent crime scene I have ever been involved in,” Waco police Sgt. W. Patrick Swanton said that day. “There is blood everywhere.”

Police seized leather jackets, weapons, and motorcycle paraphernalia, including raffle tickets for events that were supposed to happen at the meeting. More than 200 men and women in motorcycle garb (including Crump) were lined up and searched near the scene littered with dead bodies, bullet casings, and bloody motorcycles.

Meanwhile, Harris, King, and Garcia sat under a tree in the parking lot where they say officers with assault rifles approached to search them.

When King asked why, an officer purportedly answered: “Because you are wearing leather vests.”

The suit claims that Swanton told the media, in a series of interviews, that police “arrested three bikers who were carrying weapons and tried to reach the scene after the fighting had quieted down.”

Swanton, according to the suit, “tried to portray these three plaintiffs as bikers arriving with weapons as reinforcements when” in reality they were sitting in the parking lot.

Harris, Crump, King, and Garcia say they were only arrested because of their presence at Twin Peaks and because they were wearing biker “colors.” But they say they committed no crimes that day.

May 17, 2015, marked one of the largest mass arrests in a single criminal incident in American history. The men were held with zip-ties and taken to the convention center in city busses. In the end, 177 of the bikers were arrested and charged with engaging in organized criminal activity. Today, 155 of those bikers have been indicted. None have been tried yet.

Harris, King, and Garcia all had their bonds set at $2 million, while the rest of the bikers had bail set at $1 million.

“There are pending criminal matters and civil lawsuits, and the City of Waco chooses to litigate these matters in the court,” Jennifer Richie, the city’s attorney, told The Daily Beast on Tuesday.

According to their suit, the men were “unsuspectingly going to a place they weren’t wanted or liked, and where a paranoid and trigger-happy faction of local law enforcement had already been preparing for a shootout.”

Local law enforcement has said on multiple occasions that they received advanced intelligence anticipating the violence. The Bandidos and Cossacks’ dispute was over the use of “rockers” attached to their riding jackets and vests. The Cossacks were not invited to the meeting—nor a member of the confederation—but showed up anyway, according to multiple reports.

Several suits filed in the wake of the shooting allege that officials at Front Burner, which operated the Waco franchise, were warned by police before the meeting.

“What happened here today,” Swanton said at the time, “could have been avoided if we had had management at a local establishment listen to their police department and assist us.

“They failed to do that,” he added.

But victims and arrested bikers have said in various lawsuits that they still don’t understand why they weren’t warned. If the lawsuits move forward, they may get their answer.