Salzburg's Europa League match at home to FC Basel was interrupted for 12 minutes on Thursday (local time) when fans of the visiting Swiss side threw objects on to the pitch.
The referee led the teams off the field in the 30th minute after Basel fans hurled plastic bottles, cups and cigarette lighters at a Salzburg player as he went to take a corner.
Basel captain Marco Streller and club president Bernhard Heusler both approached the fans and appealed for calm and the teams returned shortly afterwards to continue the match.
Basel had defender Marek Suchy sent off in the ninth minute for a rough tackle on Alan and Streller was booked for protesting the decision.
Salzburg led 1-0 with a 20th minute goal by Jonathan Soriano before Streller equalised shortly after the interval.
The first leg in Basel ended in a 0-0 draw.
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