The suspects, who are aged between 26 and 30, were making a stop at the western city of Cologne after leaving Marseille, where the worst violence at an international tournament since the 1998 World Cup in France erupted last Saturday between Russian and English football thugs.

German police said the men acted in an "extremely aggressive and brutal manner" towards three Spanish nationals - two tourists and their guide yesterday.

The Russians "beat and kicked" their victims, leaving one seriously wounded, police said, without giving details on what sparked the attack.

Police arrested five assailants on site, but one got away.

The sixth was subsequently arrested at the Cologne-Bonn airport, where the suspects had been due to board a flight.

The men had European Championship tickets for two Russian matches against England and Slovakia, and were carrying "typical objects used by hooligans including masks and gumshields".

German police said they will contact their French colleagues to determine if the men had been involved in the fan violence that had plagued Euro 2016 in France.

A French court yesterday jailed three Russian football supporters over Euro 2016 fan unrest while a far-right Russian agitator was thrown out of the country.