Two Russia internationals have been detained by police for 48 hours to be questioned over an attack on a civil servant in a cafe in Moscow.
Zenit St Petersburg's Aleksandr Kokorin and Krasnodar's Pavel Mamaev are said to have assaulted trade ministry official Denis Pak on Monday, leaving him needing medical treatment.
The Russian Premier League said it was outraged by their "rowdy behaviour".
Police said both players had reported to a police station on Wednesday.
They had been detained over charges of hooliganism, which carries a maximum jail sentence of seven years.
In a statement, the Russian Premier League expressed "its outrage and strongly condemns their rowdy behaviour".
It added: "This act not only casts a shadow over the glorious names of FC Zenit and FC Krasnodar, but all of Russian football.
"We believe that those responsible should be punished in the most severe way. There is no place for hooligans in football."
Zenit said Kokorin had behaved "disgustingly" and Krasnodar said they were looking to end Mamaev's contract.
Mamaev, 30, has 15 Russia caps and played for CSKA Moscow 128 times before moving to Krasnodar in 2013.