Manchester City boss Pep Guardiola said Manchester United fans who singing vulgar chants about Phil Foden's mother during Sunday's game lacked class and "should be ashamed".
Guardiola questioned United supporters' integrity having also targeted the England international as he left the field following a drab goalless draw at Old Trafford.
“The chants to him? Lack of class. But it’s not United, it’s the people," Guardiola said.
“We are so exposed, the people who are now on the screen in world football – managers, owners, and football players, especially.
“Honestly, I don’t understand the mind of the people, involving the mum from Phil, being involved in that.
“It’s a lack of integrity, class – and they should be ashamed. But it’s what it is, it’s happening everywhere I would say, not just in UK, everywhere.”
City were shocked and disgusted by the chants and the number of people involved. United’s stance is that they condemn all abusive chants aimed towards players.
The stalemate meant City missed the chance to return to the top four of the Premier League while United continue to languish in 13th place.
Guardiola said: “Of course it would be better to win, but Old Trafford is Old Trafford – always you have to make a good performance [to win].
“When we lost the ball we were not good and they could run. The first 10-15 minutes of the second half were our best moments and I saw some good things but we were not in the position to hurt them more. But it’s fine. We take the point and we move forward.”

United boss Ruben Amorim was asked how difficult it will be to turn the club’s fortunes – and style of play – around.
The Portuguese said: "I can say we want to be competitive in the short space of time but to be really dominant against that type of opponent is going to take a lot of time.
"We have to use different weapons. In that way of playing [ball domination] City is maybe the best team in the world. If you compare this game against Arsenal, we have some moments we did the better today was different. We are improving. To play in this way they play for a long time.
"I’m in a rush, because we are suffering a lot. Everybody here is suffering a lot with all these changes and we have to show something in the next year, so right away.”
At the final whistle the sit-in organised by the 1958 group to protest against the Glazer family’s ownership was attended by a couple of hundred United fans.