Liverpool's fans threw bottles and fired at the bus from Manchester City, which arrived at Anfield prior to the Champions League game on Wednesday.
No one was hurt, but the BBC and other news agencies reported that the bus was so badly damaged by projectiles that it would not be able to make the return journey to Manchester.
Hundreds of Reds fans lined the streets around the floor, sang songs and waved flags before 19.45 clock start for the first quarter-finals.
The atmosphere was lively as a string of people climbed on lampposts, walls and street signs to catch a glimpse of the teams as they arrived.
The city bus is there somewhere 1945 pic.twitter.com/jBNDeDgZIz
– Anfield Leak April 4, 2018
The city first arrived, but their bus became the target for a few rockets as it slowed to navigate around the corner of Arkles Lane and Anfield, where most of the fans were gathered.
A series of red torches were also drained, making visibility difficult as trailers lined the streets outside the stadium. Moments later Liverpool came to a loud welcome.
Liverpool coach Jürgen Klopp apologized for the fans' actions and said before the game: "I really do not understand that, we tried everything to avoid such a situation. It was very positive and we did not know what happened before I was sorry for Liverpool. "
His city councilor Pep Guardiola said he believed in the bus attack on Borussia Dortmund last year, when an explosive smashed the windows, would have contained further incidents like this one ,
"I want to thank Jürgen for his words, which we did not expect [attack] after what happened in Dortmund last year," said Guardiola. I know that's not Liverpool: I know the club's history is much bigger than those four, five or ten guys.
Liverpool immediately issued a statement condemning the actions of the fans, the game that started punctually.
"The club condemns the scenes that preceded our quarter-final first leg in the Champions League, which led to it that Manchester City's team bus was damaged on its arrival in Anfield "
" We apologize unconditionally to Pep Guardiola, his players, staff and officials. The behavior of some people was totally unacceptable and the club will work fully with the authorities to identify those responsible.  "The priority now is to identify the facts and provide Manchester City with all necessary support."
Earlier, the police of Merseyside had warned that the trainers who were carrying Liverpool would be diverted to construction works and fan safety
This report used information from the Press Association