Tear gas deployed against fighting Polish fans in Marseille

French riot police use tear gas, pepper spray and batons to break up fights between Polish football fans in the southern French city of Marseille, ahead of Poland's Euro 2016 match against Ukraine.

MARSEILLE, FRANCE (REUTERS) -  Police using tear gas, pepper spray and batons broke up fights between Polish soccer fans in the southern French city of Marseille on Tuesday (June 21), detaining four of them ahead of Poland's final Euro 2016 group stage match against Ukraine.

Thousands of Polish supporters swarmed through the narrow streets of the city's Vieux Port (Old Port) district, drinking, chanting and letting off smoke bombs before the match.

Fighting erupted suddenly among a group of hardcore Polish fans and was swiftly quelled by police deployed around the waterfront.

Officers led supporters away in handcuffs, two of them near the harbour and later near the stadium, according to a Reuters photographer. A police official said the fights involved rival Polish hooligan groups.

Marseille authorities deployed about 1,000 police and 200 private security agents for the match. A surveillance helicopter hovered over the fan zone close to the stadium.

Fan violence marred the opening days of the tournament and forced European soccer's governing body UEFA to threaten England and Russia with expulsion from the championship. But disturbances have largely subsided in recent days.