The Belgian side travelled to Liverpool on Thursday night but there was an unsavoury scene in the second half.
Jurgen Klopp's side took the lead on the stroke of half-time as Ryan Gravenberch bundled in after Moris spilt Trent Alexander-Arnold's long-range strike.
Liverpool kept knocking at the door for a second but couldn't find it thanks to the goalkeeper's heroics in goal.
However mid-way through the second half, a laser was aimed at Moris' face from a member of the crowd.
The 33-year-old could be seen shouting towards the referee and pointing to it in frustration, with the laser eventually going away.
A similar incident occurred in Greece earlier in the evening when Ajax faced AEK Athens.
Former Tottenham star Steven Bergwijn had a multitude of lasers aimed at him just before he took a penalty for the Dutch giants, one that he scored despite the distraction.
Back at Anfield, Liverpool fans couldn't believe what they saw early in the match when Darwin Nunez missed a sitter.
The Reds played in a similar fashion to their opening Europa League clash against LASK when they started off slowly before scoring.
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Diogo Jota was on hand to make it game, set and match in second half stoppage-time with his finish on the break.
Liverpool sit top of their group after two games, with the result a good response to their dramatic defeat at Tottenham on Saturday.