Liverpool are facing the prospect of disciplinary action by European football authorities following an attack on Manchester City`s team bus before their Champions League quarter-final.
Missiles were thrown at the bus as it arrived for Wednesday`s first leg at Anfield, which hosts Liverpool won 3-0.
UEFA, European football`s governing body, said it would investigate the setting off of fireworks, the throwing of objects, acts of damage and crowd disturbances.
"The charges of acts of damage and crowd disturbances relate to incidents involving the Manchester City FC team bus," UEFA said in a statement.
The case will be dealt with by the UEFA control, ethics and disciplinary Body on May 31, it added.
Although the incidents took place in streets surrounding Anfield, Article 16 of UEFA`s regulations state that "host clubs and national associations are responsible for order and security both inside and around the stadium before, during and after matches".
Manchester City coach Manel Estiarte posted footage of the attack on Instagram. The sound of objects striking the vehicle can be heard in the video, filmed from inside the bus as it drives slowly towards the stadium.
His post is accompanied by the comments: "No words. Unacceptable".
British police have launched an investigation to identify those responsible while making an appeal for video evidence.
Police superintendent Paul White, the match commander, said: "Thankfully, no one on the bus was injured, but injuries were caused to two of our officers when projectiles were thrown towards the bus.
"This behaviour by a number of people who threw bottles, cans and pyrotechnics towards the bus is completely unacceptable and we will conduct enquiries to identify who was responsible and bring them to justice.
"We worked very closely with both clubs to ensure the safety of the public and the teams themselves, and it is disappointing to see that a number of people behaved in this appalling way."
White added: "Two officers sustained cuts and swelling - one was struck by an object and another suffered glass cut injuries.
"What should have been a celebratory event for thousands of people was spoilt by a number of people who threw bottles, cans and pyrotechnics."
Liverpool released a statement before the match apologising to City over the incident, saying they would cooperate with the authorities to identify those responsible.
Manchester City manager Pep Guardiola questioned the organisation of his side`s arrival at Anfield ahead of the highly-charged match.
"I didn`t expect that," he said after the game. "I am new here. Normally when the police know that is going to happen, they try to avoid it happening.
"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 not only one, only two, only three. Hopefully, it doesn`t happen again."