LAS VEGAS (AP) _ The test maker behind Common Core assessments in Nevada, Montana and North Dakota has denied a breach of contract accusation after computer problems forced a halt to the online exams in April.

Widespread technical problems with Measured Progress could mean the states won’t meet the testing mandate tied to millions of dollars in federal funding.

The New Hampshire-based company said 37 percent of Nevada students and 76 percent of Montana students completed the computerized English language arts and math tests for selected grades. A total of 88 percent of North Dakota students completed either the online or paper version.

The federal testing mandate requires at least 95 percent of students to participate _ though not necessarily complete the test. It is unclear what counts as participation. Many students had trouble accessing the test at all.

The U.S. Department of Education has not said how it will determine participation but has said there were no exceptions to the requirement.

However, recent technical problems with the online tests were unprecedented and money has never been withheld over standardized testing participation compliance.

“They haven’t given us a clear set of parameters,” said Kirsten Baesler, North Dakota’s state superintendent.

During the testing period that became a logistical nightmare, the three states offered a pass to its schools that couldn’t test online or gave up trying. Options included waiving the testing requirement in Montana, using a paper version of the test or documenting attempts in lieu of test results in the other two states.

Without knowing if logging in counts or if a certain number of questions must be answered, state officials say they don’t know if they will meet the mandate though Baesler was confident North Dakota would pass muster.

Meanwhile, the states have positioned themselves to hold the test makers accountable by discussing legal options with their state attorneys general.

Nevada, being the most severely impacted, filed breach of contract notices with Measured Progress and the test creator, the Smarter Balanced Assessment Consortium.

The consortium said it disagreed with the state’s assertion.

Measured Progress declined to comment on the breach of contract notice but said in a response to the state that staggered testing periods and additional capacity for Clark County would be a “final remedy” and make the system fully functional.

The suggested cure proved unsuccessful according to the school district and it abandoned testing altogether. The Las Vegas-based school system is the fifth largest in the country, serving about half of the state’s students.

Nevada said it is treating the issue as possible litigation. A state spokeswoman declined to comment further but said it is still negotiating for a resolution to recover costs.

“We still intend to hold them accountable,” Judy Osgood of the Nevada Department of Education said.

Nevada said it thinks hundreds of schools weren’t able to test.

Montana indicated about 82 percent of its students participated.