Eight people were arrested by police in Barcelona prior to Wednesday's Champions League tie at the Camp Nou, while police had to stop ticketless French fans from forcing their way into the stadium.
On Thursday, Le Parisien reported that four PSG fans had been taken into custody after being stopped at the border between France and Spain by police, who discovered flares in their car. One was also subject to a stadium ban.
Three PSG 'ultras' from the Boulogne Stand at the Parc des Princes were arrested after fighting in Barcelona on the night before the game.
The paper said 150 ticketless supporters, largely from the 'K-soce team' fan group, attempted to force their way into the Camp Nou before kick-off.
The group, which had approached the stadium holding lit flares, were repelled by Spanish police and dispersed in the city centre. One arrest was made.