The objects were thrown from the stadium's north stand as O'Connell prepared to take a throw-in during the first half.

United boss Chris Wilder believes the derby atmosphere has turned particularly hostile in recent seasons.

"There were some coins – it's gone quite hostile," Wilder said in his post-match interview.

"It's always been boys and rough and tumble, but, when I was a player, you knew Sheffield Wednesday players and you used to go out and have a beer.

"It's gone pretty hostile now and I don't think anybody wants to see that. I'm disappointed it's gone that way and you can't really do a lot about it."

Wednesday manager Steve Bruce also condemned the incidents.

"If that is the case and somebody threw a coin then unfortunately it's the society we live in today and we'll find them and we'll deal with it," he said.

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