The prosecution has indicted 21 cram school operators, tutors and brokers without detention for leaking U.S. Scholastic Aptitude Test materials.

Seoul Central District Prosecutors’ Office said Sunday that 14 hagwon operators and tutors, and eight brokers were questioned for illegally collecting and selling SAT questions, throwing the spotlight back on a string of cheating scandals from earlier this year. One of those questioned belongs to the military and was referred to the military prosecution.

Prosecutors said the suspects’ methods ranged from tutors recording the questions themselves, to hiring people to take the exam and memorize the questions. They also allegedly filmed the exam papers in Guam and bought questions from high-scorers. They later compiled the leaked questions into booklets for commercial use.

The investigators said one of the brokers collected up to 220.7 million won ($207,531) by buying questions from exam-takers online and reselling them to 358 people through a broker.

One of the indicted hagwon operators identified by his surname Kim bought such booklets from brokers at 47 million won ($44,000) each, the prosecutors said.

The questions were put up for sale online in booklet or individual form, with each question costing between 20,000 won and 300,000 won, they said.

SAT cheating has long been a hot social issue in Korea, where hundreds of thousands of students take the exam every year to enter U.S. colleges.

“We get hundreds of calls every week from parents who want to send their children to the so-called ‘jjokjipgae’ teachers, who make good predictions of questions that will come out in the test,” a CEO of a SAT hagwon in Gangnam told The Korea Herald, wishing to be identified only as Han.

“But people in this industry know that there’s only one way for SAT tutors to exactly foretell what will be on the next test.”

In 2007, the College Board, which organizes the U.S. college-entrance examination, cancelled some 900 SAT test-takers’ scores due to suspicions of a “security breach.”

In May, the exam was cancelled in Korea for the first time in the organization’s history, due to an alleged exam questions leak.

In response to continuing SAT cheating scandals in Korea, the board later withdrew the biology section from the June 1 session and permanently cut the number of SATs administered in the nation from six to four.

By Suk Gee-hyun (monicasuk@heraldcorp.com)