BRUSSELS (AP) — Belgian authorities say they have detained 13 people for questioning from raids linked to an investigation into match-fixing in professional tennis.

The federal prosecutor's office says in a statement on Tuesday there were 21 searches, most of them in the capital Brussels.

Prosecutors suspect a Belgian-Armenian crime gang has been trying since 2014 to corrupt lower division matches on the Futures and Challenger circuits, where there are few cameras filming tournaments.

No names of any players suspected of links to the match-fixing were provided.