Bottles, cans and firecrackers were thrown at the bus as it made its way to the ground and though nobody on the bus was injured, the front window was smashed, rendering the vehicle unfit for use.
City were forced to source a new mode of transport for their journey home and Merseyside Police later confirmed that two of their officers were harmed by projectiles in the clashes.
Liverpool issued an unreserved apology for the incident before kick-off, condemning the “completely unacceptable” scenes outside Anfield “in the strongest possible terms”. Uefa, European football’s governing body, are expected to launch an investigation into the matter.
Guardiola, who saw his side defeated 3-0 on the night, said he had not expected to see such behaviour from supporters of a club as “prestigious” as Liverpool.
The City manager also compared the incident to last year’s Dortmund bus bomb attack, in which three roadside bombs were used with lethal intent on a vehicle carrying the Borussia Dortmund team.
“Yesterday you explained, I am new here, that it is going to happen. Normally when the police know it is going to happen, they tried to avoid it from happening,” he said. “So I did not expect that from the Liverpool side, their people.
“One year ago something happened in Dortmund so we come here to play football and I don't understand this kind of situation.”
Guardiola added: “The bus is destroyed but I did not expect a prestigious club like Liverpool doing this kind of thing.
“It is not Liverpool, it is the people, only one, two or three but hopefully it does not happen again.”
City’s travel arrangements attracted much pre-match attention, with Liverpool supporters encouraged on social media to line the roads around Anfield and give both team buses a lively reception.
Liverpool stressed that fans should show their support “in a friendly, respectful and considerate manner” and earlier on Wednesday, Merseyside Police announced that the buses’ routes would be changed due to “building works and to ensure the safety of fans”.
Before the game, Jurgen Klopp, Guardiola’s Liverpool counterpart, apologised for the scenes outside Anfield.
“I really don't understand it,” he said. “We tried everything to prevent a situation like that. When we came through it was obviously very positive. For Liverpool FC I have to say sorry.”
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