Chief Constable of Merseyside Police Andy Cooke has branded Liverpool fans "criminal" for celebrating their title triumph on Friday night.
Social media images showed a firework hitting the Liver Bird building, one of the city's most famous landmarks, during a second night of celebrations on Friday.
Following the gathering, volunteers started helping to clean up the streets of the city. This allowed police to break up crowds that gathered on the Pier Head after part of the Liver Building caught fire amid the wild celebrations.
Fifteen people arrested on suspicion of violent disorder have been bailed while investigations continue. This is not acceptable.
"In addition, the actions of the minority were not only irresponsible but criminal".
"The crowd largely dispersed by about 1.30am and a short time later officers were confronted by a group of people more than 100 strong who sought confrontation with the police", Roy said.
"Our city is still in a public health crisis and this behaviour is wholly unacceptable".
Premier League champions Liverpool were forced to criticise their fans' "wholly unacceptable" behaviour after police claimed glasses and bottles were thrown at them during title celebrations that turned violent.
'I cannot stress enough that these gatherings put an unnecessary strain on our emergency services and could mean that we might not be able to get to other people who really need us, ' Cooke added.
"When the time is right we will celebrate", Klopp told fans in a letter published by the Liverpool Echo.
"We are going to do the guard of honour, of course", the Spaniard said, as quoted by AS.
Mayor of Liverpool Joe Anderson shared a video of the violence and said that 300 fans "fought for over two hours" with police before it all subsided in the early hours of Saturday morning.
"I appreciate LFC fans want to celebrate but please, for your own safety, and that of others, go home and celebrate at home", Anderson said on Twitter.
"When it is safe to do so, we will all work together to arrange a victory parade when everyone can come together to celebrate".
Liverpool have wrapped up the title this season with seven games to spare, as they sit 23 points clear of the chasing pack, and will be given a guard of honour by the side they have dethroned when heading to the Etihad Stadium for a meeting with Guardiola's City on Thursday.