By Philip O'Connor and Philip Blenkinsop

LILLE, France (Reuters) - Beer-swilling English soccer fans bathed in public fountains on Thursday evening in the northern France town on Lille to celebrate their team's victory over Wales in nearby Lens, with little sign of the tensions seen there in previous nights.

Police were braced for the kind of violence that threatened England and Russia with expulsion from the tournament and led to the use of tear gas on Wednesday to disperse rowdy English fans in Lille.

But on Thursday, fans flooded back from Lens singing and playfully kicking a soccer around as they exited Lille's rail station. Occasional showers of rain also helped keep the atmosphere calmer.

A Reuters photographer saw police detain one of a group of fans who were fighting in Lille. In general, though, police kept a low profile while monitoring what had in recent days been a meeting point, and an occasional flashpoint, for fans.

"It's OK. They're just in high spirits. As long as it stays that way, no problem," one police officer said.

Thursday afternoon's Group B match between England and Wales in the Euro 2016 group has been dubbed "The Battle of Britain".

After violence in the Mediterranean port of Marseille before and after England's 1-1 draw with Russia on Saturday, UEFA had warned England that a repetition of fans' violent behavior could see the team expelled.

UEFA has also told Russia that it would be disqualified if there was a repeat of its fans' violent behavior, which included attacks on England supporters in the stadium as the match ended.

Throughout Wednesday, 36 people were arrested for various offences as Russia lost to Slovakia in Lille and England prepared to play Wales, police said. That included 13 British nationals, police said.

UEFA said on Thursday it regretted the previous night's violence, but it stopped short of action to punish the fans or the teams.

RESPECT

On Thursday morning, police checked fans boarding trains from Lille to Lens to ensure none were traveling with alcohol, leading to long queues. A heavy police team carried out similar checks in pouring rain on arrival 45 minutes later in Lens.

Martin Glenn, the chief executive of England's Football Association, had urged England fans to show "consideration and respect" as French police were already pre-occupied with preventing any militant attacks.

France has suffered several attacks by Islamist militants in the past two years, including a shooting rampage in Paris in November that killed 130 people. Two French police officials were killed on Monday by a man claiming allegiance to Islamic State.

Separately, police in Lyon in southeast France said two fans suffered stab wounds in a fan zone there on Wednesday.

Lyon police said one of those wounded, a Frenchman, had told them one of his attackers wore an Albania soccer shirt. France beat Albania 2-0 in another of Wednesday's games.

Marseille police said a further 20 Russian fans were to be expelled from France, including Alexander Shprygin, the head of a Russian supporters group.

(Additional reporting by Lucien Libert in Lens, Gerard Bon, Chine Labbe, Julien Pretot in Paris and Catherine Lagrange in Lyon, Wolfgang Rattay; Writing by Andrew Callus and Ingrid Melander; Editing by Larry King)