Moscow (AFP) – Russian arch-rivals Spartak and CSKA were each fined nearly $8,000 on Wednesday over fan violence that halted their Moscow derby at the weekend and shone another damning spotlight on the World Cup host.

The latest crowd trouble to tarnish Russian football erupted on Saturday when Spartak and CSKA supporters clashed at Spartak’s Otkrytie Arena, a 2018 World Cup venue, forcing the referee to stop the match for five minutes in the second half.

Police said that 70 people were detained after flares were thrown in the stands, while riot police waded in as rival supporters tried to scale metal fencing to confront one another.

Artur Grigoryants, head of the Russian Football Union’s disciplinary board, said the bulk of the fines — 500,000 rubles for Spartak and 490,000 rubles for CSKA — was linked to fans’ use of flares and other pyrotechnics, Russian news agencies reported. 

Deputy Prime Minister Arkady Dvorkovich has said he was “ashamed” by the violence, Russian news agencies reported. 

Russian authorities have called for measures to curb crowd trouble as the country prepares to host the World Cup. 

In July President Vladimir Putin approved a law that tightens security controls at stadiums and will see the interior ministry publish online a blacklist of supporters banned from matches. 

Russian supporters were widely blamed for outbreaks of violence that tarnished Euro 2016 in France, notably in Marseille, where they clashed with England fans.