PARIS — Hooliganism is making a comeback, and the timing could be bad with four high-risk matches in the first week of the European Championship in a country where the police force is already under a huge strain.

Should one or more of these matches – England vs. Russia in Marseille on June 11; Turkey vs. Croatia the next day; and England vs. Wales and Germany vs. Poland on June 16 – descend into violence, the soccer itself could quickly become overshadowed.

Police forces in France have been stretched since November’s terror attacks that killed 130 people.

The last thing French authorities need is thugs causing mayhem. But in the last two months alone there’s been a soccer violence increase around Europe.

At the French Cup final, fans managed to sneak flares and objects into the Stade de France despite a security wall and triple security checks, and others tried to invade the field, raising serious concern ahead of Euro 2016, where the opening match between France and Romania takes place June 10.

In Germany, several hundred fans from Dynamo Dresden were held back by riot police to stop them attacking bitter rivals Madgdeberg in a third-division match in April, and mass arrests were made in May during the troublesome local rivaley between Frankfurt and Darmstadt.

In the League One playoff final Sunday in London, fights broke out among supporters; Rangers and Hibernian fans poured onto the field to fight in the Scottish Cup final at Glasgow – a throwback to the mid-1980s when hooliganism blighted Britain – Liverpool and Sevilla fans traded punches in the Europa League final in Switzerland; FC Zurich thugs charged down the tunnel last Wednesday to try to attack their own players following relegation from the Swiss Super League, then battled riot police outside.

Although centered on inter-club rivalries, these troubles highlight how hooliganism has been creeping back after several years.

In November, 2014, Francisco Javier Romero Taboada, 43, a Deportiva fans in Spain, died after emergency services rescued him from a river where he was dumped after being heavily beaten during a fight against rival hooligans from Atletico Madrid.

This season the Europa League was hit with violence. Heavy fighting at night between Italian side Napoli and Polish club Legia Warsaw, street battles between Spanish side Athletic Bilbao and Marseille; city center riots in Amsterdam between Ajax and Turkish club Fenerbahce. Other trouble involved Lech Poznan from Poland; Belgian side Anderlecht, and Moscow-based sides CSKA, Lokomotiv and Dinamo.

A further 10 matches at Euro 2016 are identified as risky – including Germany vs. Ukraine; Slovakia vs. England and Russia vs. Wales – and there will be increased border controls and tighter security at train stations and airports, in addition to eight police spotters from each country who will identify potential hooligans.

“All of those who are subject to a banning order will be prevented from leaving their country by their local police in so far as their legislation allows,” said Antoine Boutonnet, the head of French police’s anti-hooliganism division. “Furthermore, we have gathered information on potential risks and will continue to do so during the tournament.”

But hooligans show determination and ingenuity to avoid police detection.