The entrance to the former Auschwitz-Birkenau Nazi concentration camp on Jan. 25, 2015. (Joel Saget/AFP via Getty Images)

For an Israeli schoolchild, a trip to Poland to see World War II Nazi death camps can be a vital part of their education about the history of the Jewish faith and the Israeli state. For parents, however, it can be an expensive burden.

A few months ago, Israeli authorities began to covertly investigate the differences in prices between a number of tour operators offering these trips. They concluded that something was amiss. Now, the Israel Antitrust Authority has announced that nine tour operator executives have been arrested on suspicion of running a secret price-fixing ring that was aimed at artificially inflating the cost of trips to former Nazi death camps such as Auschwitz.

At least six tour operators are being investigated on suspicion of involvement in the alleged cartel. In some cases, the homes of company executives were searched and property confiscated. According to the publication Haaretz, one of those detained is also suspected of bribery.

The cost of these trips had long caused controversy within Israel. The project to send Israeli schoolchildren to Poland first began in the late 1980s, and it is estimated that about half of the Jewish schools in Israel offer the journeys to their pupils. The trips are sponsored by the Education Ministry and form part of the Holocaust curriculum, with students visiting Auschwitz and other World War II death camps, in addition to learning about the modern-day Jewish community.

However, the trips have long had a reputation of being expensive and affordable only for the most well-off families: In 2011, the Jerusalem Post reported that the trips cost as much as 5,400 shekels, which would currently convert to more than $1,300, leaving many students from poorer backgrounds unable to participate. Although the government has since moved in to subsidize the trips, reports in the Israeli press suggest that they can still cost thousands of shekels — or at least $500 or so.

The trips had also caused some controversy within Poland because of the extensive security operations put in place for the students.

The Israeli government had given a number of tour operators the tenders for the business of flying high school students to Poland. In theory, these companies would be in competition: The schools were supposed to negotiate among the companies to find the best deal. The investigation found that in practice, however, the prices appeared to be fixed among the companies. Although the operators appeared to offer discounts to schools, investigators say, these discounts were secretly coordinated and there was no real competition.

Authorities say that the scam came to light after a tip and that it was unclear how far up the chain of command knowledge of the practice went. Israeli parents are likely to be outraged that a trip designed to be solemn and respectful is being exploited in this manner.

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