“The behaviour of a number of individuals was completely unacceptable and the club will cooperate fully with the authorities to identify those responsible.”

Fans let off red flares and sang their club’s songs before the City coach arrived and beer cans were thrown at the bus. At least one bottle was thrown and smashed on the side of the bus but did not appear to break any of its windows.

City manager Pep Guardiola, whose team lost the match 3-0, was disappointed by the incident.

“Normally when the police know that is going to happen, they try to avoid it happening. I did not expect that from the Liverpool side, from the people,” the Spaniard said.

“One year ago, something happened in Dortmund,” he said, referring to the attack, with explosives, on Borussia Dortmund’s team bus before a game against Monaco.

“We come here to play football and I don’t understand this kind of situation,” he said, adding that no players had been hurt.

“Nothing happen, the bus is destroyed. I didn’t expect that a club as prestigious as Liverpool would do these kind of things. Of course, it is not Liverpool, it is the people – it was only one, only two, only three. Hopefully, it doesn’t happen again,” he said.

European soccer’s governing body Uefa is likely to investigate the incident and Liverpool could face financial sanctions.