MINNEAPOLIS (WCCO) — It wasn’t just a computer glitch that caused the state to temporarily halt the annual school test known as the MCAs.

It was a deliberate attack on the system.

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The Minnesota Department of Education says it has a contract with a company called Pearson, which works with school districts nationwide in administering online standardized tests.

Officials say they discovered evidence Tuesday of what’s called a “distributed denial of service attack,” or DDOS.

That means someone on the outside deliberately disrupted the online MCAs, as well as tests in other states.

The MCAs, or Minnesota Comprehensive Assessments, are given to students in grades 3 through 8 in reading, math and science. Students in their sophomore and junior years of high school also take the tests.

But both this week and last week, students struggled to log in.

“Someone gave me the analogy today of this type of attack,” said Josh Collins, a spokesperson for the Department of Education. “If you are in line at the grocery store and you are trying to pay and your son is going, ‘Mom, Mom, Mom, Mom,’ that is a denial of service attack.”

The company that administers the tests first discovered a server failure. Then there was a problem with too much traffic at one time.

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On Tuesday, the company found out an outsider was deliberately disrupting the system, overwhelming it so that students couldn’t log in and take their tests.

“It is not an attempt to steal data or hack into the system,” Collins said. “Rather, it is an attempt to overwhelm it so that it can’t function. This is something someone intentionally did to disrupt it from the outside.”

He says there is no indication any student data was taken.

MCA scores are seen as an indicator of a student’s growth year to year. They’re also used to track the progress of a school.

Teachers worry the technical problems have created more anxiety for students who understand the tests are important.

“Testing can already be an anxious time for students,” Collins said. “We know that, so anything that potentially increases that anxiety is concerning to us. That’s part of the reason we decided to suspend testing.”

On Wednesday afternoon, the Department of Education notified school districts that MCA testing will resume on Thursday.

The department says Pearson has assured them the problems have been fixed and the company has put new protections in place to prevent a similar attack on the testing system.

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An investigation is taking place to find the person or people responsible for the attack.