Salah sends Liverpool eight points clear after Southampton scare
Videos posted on social media show Chelsea supporters being hit by stewards with batons and forced backwards as they tried to enter and leave the Camp Nou.
Barcelona beat Antonio Conte’s side 3-0 in the second leg to win the tie 4-1 on aggregate.
Chelsea released a statement on Thursday, which read: “The incidents were brought to the attention of UEFA immediately and information we collect will form the basis of a report the club will send to the relevant authorities and organisations.”
After the game, Chelsea requested those affected to contact the club and a spokesman said they were “aware” of the incidents that took place.
Barcelona are responsible for security around their stadium and if found to have been at fault, the Spanish club could face a fine from UEFA.
A UEFA spokesman has said it is still gathering evidence before taking the matter forward.
Tension between football fans and security officials in Spain is high, after a police officer died amid riots before a Europa League fixture between Athletic Bilbao and Spartak Moscow last month.
Last year, eight Leicester supporters were arrested by Spanish police before the team’s Champions League quarter-final with Atletico Madrid.
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