Spanish police have arrested 34 people as part of a match-fixing network.

Six of the 34 people arrested are low-level tennis players ranked between 800 and 1,400 in the world. Authorities did not name the players arrested.

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The investigation, which dates back to 2013 centers on at least 17 match-fixing cases in Spain and Portugal. The network is believed to have generated more than €500,000 in the match-fixing cases.

All of those arrested are Spanish, authorities say.

"Sometimes they promised €500 and in the end only paid €50. The players were above all the victims," a police spokesman told AFP.

Photo credit: Mark Peterson/Corleve.