Flares thrown by Galatasaray supporters twice interrupted Tuesday's Champions League game at Borussia Dortmund.
The visiting fans set off firecrackers, smoke bombs and flares starting early in the match, won by Dortmund 4-1.
Some flares landed in the section of Dortmund fans and the match was close to being abandoned as the referee waited until they were cleared.
The match was twice stopped in the second half as flares were thrown on to the pitch and set off in the stands.
The first of the delays came when flares were thrown on to the sidelines of the pitch where the substitutes had been warming up.
After Dortmund scored their final goal in the 85th minute, another flare in the crowd caused a temporary halt, and by the finish both sides were keen to get off the pitch.
Dortmund coach Jurgen Klopp was screaming for the match to be stopped late on as further firecrackers could be heard around the ground.
Klopp said the behaviour of the visiting fans was "pure provocation."
"It was incredible," Klopp said. "We took all the security steps but it still happened."
Galatasary have already been fined 50,000 euros this season after fireworks and missiles were thrown on to the Emirates Stadium pitch during Arsenal's 4-1 Champions League win on Oct. 1.
UEFA also instructed the Turkish club to pay damages to Arsenal, who were cleared after originally being charged with "insufficient organisation (lack of body searching)."
On Tuesday, there were disturbances after the final whistle, too. One Galatasaray fan ran onto the field but was hugged by Dortmund's Ilkay Gundogan, himself of Turkish roots, and escorted off the pitch. Gundogan gave the fan his shirt.