Chelsea confirmed after the 2-0 win that they were 'looking into' allegations City's players and Foy were targeted during the game.
Incidents of fans aiming laser pens at players and match officials have increased in recent years.
In March 2008, UEFA fined Lyon ?2,520 after Manchester United's Cristiano Ronaldo was targeted with a laser pen during a Champions League game at the Stade Gerland.
In the line of fire: A laser appears to be shone on referee Chris Foy
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