Planned Parenthood and the American Civil Liberties Union (ACLU) asked a federal court to block an Arizona law defunding Planned Parenthood, arguing in a legal challenge filed Thursday that the Arizona measure is “illegal.”

The GOP-backed law, signed by Republican Gov. Doug Ducey in May, specifically targets abortion providers, excluding any facility from Medicaid that fails “to segregate taxpayer dollars from abortions, including the use of taxpayer dollars for any overhead expenses attributable to abortions.”

Federal law already bars state Medicaid funds from using federal dollars for abortion care, except in cases of rape, incest, or life endangerment.

In an 18-page complaint, the plaintiffs argue that the restriction is impermissible under Medicaid statutes, and they ask for an injunction on the law, which goes into effect August 6. Planned Parenthood said in an emailed statement that the law could slash funding for birth control, cancer screenings, and preventive care, affecting more than 2,500 Medicaid patients in the state.

The Arizona Health Care Cost Containment System, the state Medicaid agency, did not respond to a request for comment.

Jennifer Lee, staff attorney at the ACLU, called the Arizona law “another attempt to intimidate doctors who provide abortion and to punish low-income women in particular,” in a statement announcing the lawsuit. Planned Parenthood operates 11 medical centers in the state, including three in underserved and impoverished communities with high rates of infant mortality, according to the court filing.

At least ten states, including Arizona, have attempted to strip Planned Parenthood of funding—the fallout from a string of deceptive smear videos masterminded by David Daleiden, the head of the anti-choice front group the Center for Medical Progress, who now faces a felony record-tampering charge.

“This case is about the people who rely on us for basic care every day,” said Cecile Richards, president of Planned Parenthood Federation of America, in an announcement of the Arizona suit. “We’ll continue fighting in Arizona, and anywhere else there are efforts to block our patients from the care they need.”

The Arizona law represents the state’s second attempt to defund Planned Parenthood. In 2014, the Ninth Circuit Court of Appeals affirmed a lower court decision finding a similar defunding measure, HB 2800, violated federal Medicaid law.

In April, the federal Centers for Medicare & Medicaid Services sent a letter to all 50 states saying that cutting funding to qualified providers solely because they provide abortion care violates federal law.

Independent analysis suggests gutting Planned Parenthood funding exacts a toll on health care.

A 2015 report from the Congressional Budget Office indicated that health-care access would suffer under Planned Parenthood funding cuts, with the potential for $650 million in additional Medicaid spending over a decade and thousands of more births.

In Texas, births surged 27 percent among low-income women who were using injectable birth control but lost access to the service when the state cut Medicaid funding to Planned Parenthood, according to a study published in the New England Journal of Medicine.