The Ministry of Internal Affairs for St. Petersburg and Leningrad region said it was investigating a Saturday incident in which about 30 soccer hooligans fought briefly near a subway station, RIA Novosti reported.
"Around [1 p.m.] police received a report of a group fight at the Chkalov metro station," the ministry said. "Upon arrival, police details found no one present due to the brevity of the conflict."
Preliminary reports indicated it was a melee involving about 30 people, the ministry said.
The official statement said the fight happened in a square across the street from the station and that police are actively looking for participants of the fight.
Soccer fans posting on the Internet said the fight was between backers of the FC Zenit St. Petersburg and Spartak Moscow soccer clubs, with combatants wearing Zenit's blue-white-blue and Spartak's red-and-white, the Russian daily Komsomolskaya Pravda reported.
A witness identified only as Alex said brawlers wore bandages around their fists as makeshift boxing gloves, which usually indicates the involvement of organized "okolofutbolnoy" soccer hooligans.
"Young men, 17 or 19 years old, around 30 of them, were fighting," he told the newspaper. "On their hands were wound bandages. The fight did not last long, and where they went when they left, I don't know."
Police were trying to sort out the circumstances of the mass brawl by interrogating witnesses such as passers-by, employees and vendors in nearby subway kiosks and shops.
The fight was similar to a July 7 conflict in St. Petersburg in which 50 brawlers fought near the Sennaya Sqaure subway station involving fans of Dynamo St. Petersburg -- including the "Nevsky Syndicate" and "Mobile Group" fan clubs -- and Tula Arsenal, Komsomolskaya Pravda said.
That battle featured mixed martial arts-style fighting with brawlers wearing makeshift gloved and mouth guards, ending with the arrests of seven people. The detainees were released a day later.
Another brawl broke out in August 2012 at St. Petersburg's Moskovskaya metro station when a crowd of local fans descended on supporters of FC Anzhi Makhachkala, with 50 men beating 16 fans of the Dagestani club. The attackers claimed it was revenge for the 2004 Beslan school hostage crisis, which ended with the deaths of more than 380 people.
The same month saw a similar clash between Zenit and Spartak fans on a St. Petersburg street corner, in which the participants wore no club colors to avoid attracting police attention, the newspaper said. Fifteen people were detained in that incident, but again, all of them were released.
Last month, the Russian Federation Council approved the compiling of "blacklists" of soccer hooligans and toughening penalties for offenders, Interfax reported.
The law provides for fines of up to $450 for violators and a new form of punishment -- an administrative ban on visiting matches for up to seven years for particularly persistent offenders.
Under the new law, the Russian government also approved the rules of conduct for fans and will now maintain a list of people who are prohibited from visiting official sports competitions.