FIFA has filed a criminal complaint in Switzerland against online ticket platform Viagogo in its crackdown on unauthorized World Cup sales at marked-up prices.
FIFA said on Tuesday it joined other parties filing criminal complaints against alleged "opaque and deceptive business conduct" by Viagogo in the so-called secondary market.
The legal action filed on Monday was "based on a breach of the law on unfair competition against Viagogo AG with the public prosecutor's office in Geneva," soccer's world governing body said in a statement.
"FIFA's ultimate objective in the fight against the secondary ticket market is to prioritize the safety and security of fans and enforce a fair 2018 FIFA World Cup ticketing pricing scheme," it said.
Fans who buy through unofficial platforms, including Viagogo, for World Cup games in Russia face being denied entry to stadiums.
FIFA said it would cancel all tickets it identified as being traded through unauthorized sellers.
Viagogo's website was still selling World Cup tickets on Tuesday, including single seats for the June 14 opening game at more than double face value.