BISMARCK, N.D. (AP) — A federal judge in North Dakota on Monday blocked the state's voter identification law after it was challenged by a group of American Indians, who alleged that the state's voter identification requirements are unconstitutional and "disproportionately burden and disenfranchise Native Americans."

U.S. District Judge Daniel Hovland issued a temporary restraining order, ruling that the state's "ill-advised" repeal of "fail-safe" provisions in 2013 resulted in an undue burden on Native Americans trying to vote.

"There are a multitude of easy remedies that most states have adopted in some form to alleviate this burden," the Bismarck-based judge wrote.

The lawsuit was filed in January against North Dakota Secretary of State Al Jaeger by seven members of the Turtle Mountain Band of Chippewa. The tribe receives one-quarter of all welfare payments in the state, according to tribal officials.

The lawsuit is backed by the Colorado-based Native American Rights Fund, along with Bismarck attorney Tom Dickson.

North Dakota is the only state without voter registration, but state law has required voters to provide ID since 2004. Before that, casting a ballot was an informal process in most precincts, and identification cards were seldom requested.

North Dakota now requires a driver's license as identification or identity cards issued by the state, long-term care facilities or North Dakota's American Indian tribes. All must have a valid address.

Before 2013, if a voter lacked an ID card but a poll worker had firsthand knowledge of the person's identity and residence, the voter was allowed to cast a ballot. The voter also could sign an affidavit attesting to his or her eligibility to vote in the precinct.