One day after Illinois Attorney General Lisa Madigan declared daily fantasy sports betting illegal in the Prairie State, on Thursday, separate lawsuits were filed by Boston-based DraftKings and New York-based FanDuel against the AG.

The lawsuit filed in the Cook County Circuit Court in Chicago by DraftKings contends Madigan’s action “has set off a chain of events that — if unchecked — will unjustly destroy a legitimate industry,” The move by Madigan follows decision in Nevada and New York that determined the online sites to be illegal gambling. Season-long fantasy sports operator Arizona-based Head2Head Sports LLC, along with FanDuel, filed its lawsuit in Illinois’ Sangamon County where state lawmakers will work towards regulating the contests, according to the Associated Press.

The season-long version of fantasy sports has been avoided for the most part by states reviewing the legality of the daily contests. Traditional fantasy sports differ from daily fantasy sports because the latter are played over short periods of time, ranging from a day to a week rather than an entire season. Predetermined prizes are based on the overall performances of real players chosen for virtual teams.

The two daily fantasy sport industry leaders contend that contests on their sites are games of skill, not luck, and thereby allowed by state law. Madigan interprets the law differently. The DraftKings complaint requests an expedited opinion from the court declaring the games do not fall outside of Illinois law, and nullifying Madigan’s Wednesday opinion letter. Madigan pointed out in the opinion letter that while Illinois law does allow prizes or compensation for “actual contestants,” fantasy gamblers are not included, according to the Chicago Sun-Times.

Wednesday after Madigan’s opinion FanDuel issued a statement saying it disagrees with the AG’s opinion and that lawmakers should “give back to the people of Illinois the games they love.” The statement also said, “For now, we intend to continue offering play in Illinois until there has been a decision from a court on our lawsuit.”

DraftKings and FanDuel have been asked by Madigan to amend the sites terms of use to include Illinois residents to those in Arizona, Iowa, Louisiana, Montana, Nevada and Washington who already are ineligible for prizes. According to the court filing, residents of the state make up 10 percent of DraftKings customer base; one of the largest in the nation.

In October, legislation to legalize the contests was introduced by Riverside Democratic Rep. Mike Zalewski. Players would be required to be reviewed for tax debts or child support and be 18 years of age to participate in contests.