UEFA has opened an investigation into Turkey's Merih Demiral, who scored both goals in the 2-1 win over Austria in the round of 16.
Demiral celebrated his second goal with the so-called "wolf salute", the hand signal of the "Grey Wolves", who are considered nationalist and fascist.
In Turkey, supporters of the right-wing extremist "Ülkücü movement" are referred to as "Gray Wolves". The wolf salute is banned in Austria.