The lawsuit filed by at least 39 students in South Korean capital Seoul seeks damages of 20 million won each (around £12,000), the BBC reports.

South Korea’s Suneung is both important and notoriously difficult, and the country grinds to a virtual standstill on the day high school students take the test.

According to the lawsuit, invigilators at the aggrieved students’ test site rang the bell to end the Korean language part of the exam 90 seconds early.

Students protested, but their exam papers were still taken away. Much later, invigilators appeared to acknowledge the error and gave students their 90 seconds — too late to avoid significantly disrupting the exam, the lawsuit claims.