Manchester City boss Pep Guardiola said members of the Anfield crowd threw coins at him during his side's 1-0 Premier League defeat at Liverpool.
Guardiola said the objects were thrown in his direction after Phil Foden had a goal disallowed by VAR as City's unbeaten start to the season ended.
"The crowd tried but they didn't touch me," Guardiola told BBC Radio 5 Live. "Maybe next time they will be better."
Liverpool have also opened an investigation into the coin throwing.
A club spokesperson said: "We are aware of an incident involving objects being thrown into the technical area at today's game. This is totally unacceptable behaviour and not the standards of behaviour we expect at Anfield.
"This incident will be fully investigated using CCTV and those found guilty will be punished, including a lifetime ban from Anfield Stadium and a possible football banning order."
