A deeply divided Supreme Court is allowing a Texas law that bans most abortions to remain in force, for now stripping most women of the right to an abortion in the nation’s second-largest state.

The court voted 5-4 to deny an emergency appeal from abortion providers and others that sought to block enforcement of the law that went into effect Wednesday. But the justices also suggested that Wednesday’s order likely isn’t the last word on whether the law can stand because other challenges to it can still be brought.

The Texas law, signed by Republican Gov. Greg Abbott in May, prohibits abortions once medical professionals can detect cardiac activity, usually around six weeks and before most women know they’re pregnant.

It is the strictest law against abortion rights in the United States since the high court’s landmark Roe v. Wade decision in 1973 and part of a broader push by Republicans nationwide to impose new restrictions on abortion. At least 12 other states have enacted bans early in pregnancy, but all have been blocked from going into effect.

The high court’s order declining to halt the Texas law came just before midnight Wednesday.

“In reaching this conclusion, we stress that we do not purport to resolve definitively any jurisdictional or substantive claim in the applicants’ lawsuit. In particular, this order is not based on any conclusion about the constitutionality of Texas’s law, and in no way limits other procedurally proper challenges to the Texas law, including in Texas state courts,” the unsigned order said.

Chief Justice John Roberts dissented along with the court’s three liberal justices: Justice Stephen Breyer, Justice Sonia Sotomayor and Justice Elena Kagan. Each of the four dissenting justices wrote separate statements underscoring their disagreement with the majority.

Texas lawmakers wrote the law to evade federal court review by allowing private citizens to bring civil lawsuits in state court against anyone involved in an abortion, other than the patient. Other abortion laws are enforced by state and local officials, with criminal sanctions possible.

After a federal appeals court refused to allow a prompt review of the law before it took effect, the measure’s opponents sought Supreme Court review.

In a statement early Thursday after the high court’s action, Nancy Northup, the head of the Center for Reproductive Rights, which represents abortion providers challenging the law, vowed to “keep fighting this ban until abortion access is restored in Texas.”

“We are devastated that the Supreme Court has refused to block a law that blatantly violates Roe v. Wade. Right now, people seeking abortion across Texas are panicking — they have no idea where or when they will be able to get an abortion, if ever. Texas politicians have succeeded for the moment in making a mockery of the rule of law, upending abortion care in Texas, and forcing patients to leave the state — if they have the means — to get constitutionally protected healthcare. This should send chills down the spine of everyone in this country who cares about the constitution,” she said.

Texas has long had some of the nation’s toughest abortion restrictions, including a sweeping law passed in 2013. The Supreme Court eventually struck down that law, but not before more than half of the state’s 40-plus clinics closed.

Even before the Texas case arrived at the high court the justices had planned to tackle the issue of abortion rights in a major case after the court begins hearing arguments again in the fall. That case involves the state of Mississippi, which is asking to be allowed to enforce an abortion ban after 15 weeks of pregnancy.