Glen Oaks High School, seen August 29, 2018 after classes were dismissed because of a water main break.

A handful of seniors at Glen Oaks High School in Baton Rouge won’t walk with their graduating class next week after state regulators flagged online tests in American history for potential plagiarism, school officials reported Thursday.

“To my knowledge it was truly an isolated incident,” said Andrea O’Konski, chief of academic programs for the East Baton Rouge Parish school system.

O’Konksi said her office was alerted by the Louisiana Department of Education earlier this week that the answers supplied by five Glen Oaks High students on the LEAP 2025 U.S. history last month look like they might have been plagiarized.

“(State officials) have programs that flag tests. They look to see if certain words line up,” she explained. “If they see irregularities, they let us know.”

The students involved were questioned Thursday afternoon and the teacher who oversaw the class is scheduled to be interviewed Friday, O’Konski said.

Of five students flagged, one appears to have met all graduation requirements, but the other four won’t be able to graduate with the class of 2019 next Wednesday, said Taylor Gast, a spokeswoman for the school system. Those four students will have a chance to go to summer school, retake the history test and, if they pass, they can walk at the school system’s summer graduation ceremony, she said.

As per Louisiana’s graduation requirements, students have to pass either the biology or U.S. history standardized test in order to get their diploma, O’Konski said.

Biology is given in sophomore year and U.S. history is given in junior year. Both are part of new series of standardized tests, known as LEAP 2025, that is replacing end-of-course exams that public high schools administered for years.

O’Konski said the students in question were likely all retesters, meaning they’d taken the history test before, perhaps as many as three times before. She said the state puts top priority on processing the results of online tests taken by graduating seniors so they can know early enough whether they can graduate with their peers.

Follow Charles Lussier on Twitter, @Charles_Lussier.