The French government must ask itself “searching questions” after the “deeply disturbing” violence at Euro 2016, the Home Secretary said yesterday, as it emerged that authorities failed to arrest any of the Russian hooligans who clashed with England fans.

More than 150 Moscow Ultras, described by police as “hyper-violent”, are feared to be plotting further attacks on Welsh and English fans in Lille after police were overwhelmed by scenes of violence inside and outside the Marseille stadium.

Yesterday six England supporters, including a psychiatric nurse and an apprentice engineer, were jailed for at least a month each and banned from France.