Former Liverpool manager Jurgen Klopp led the way on Tuesday with well-wishes to those injured when a car ploughed into supporters at the club's trophy parade earlier in the week.
More than 50 people were treated for injuries and 11 remained in hospital on Tuesday night in a stable condition.
Speaking on Tuesday night, Klopp said: 'Yesterday just showed the two faces of life.
'The most beautiful face for a long, long time. The parade was incredible, the mood was incredible and from one second to the other, everything changed.
'There are more serious things in the world than football and thoughts and prayers go to the injured people and to the families of course. It should have been one of the greatest days in the history of the city.'
Liverpool called off further celebrations on Tuesday. Captain Virgil van Dijk said: 'Praying for a speedy recovery for everyone who suffered injuries. We are with you all.'
Klopp had earlier said via social media that his prayers were with the Liverpool fans injured and affected by the horrific scenes that unfolded on Monday.
The Reds celebrated their title triumph with an open-top bus parade through Liverpool but the day was marred when a car collided with a crowd of fans in the centre of the city.
The shocking incident unfolded just after 6pm on Water Street after thousands of fans had packed the streets to celebrate their team's triumphant season.
Emergency services rushed to the scene within minutes, and dramatic images showed police cordons, litter strewn across the road, along with a strong presence of officers, ambulances and even a fire engine.
The car, described by witnesses as 'beeping' as it made its way through the crowds, eventually came to a halt at the scene.
A '53-year-old white British man from the Liverpool area' was swiftly detained by police, who said the incident was not being treated as terrorism.
An ambulance team later confirmed that 27 patients were taken to hospital including four children. 20 people were treated at the scene for minor injuries but did not require hospital treatment. Two people, including one child, have sustained serious injuries, while four people trapped under the car were rescued by firefighters.
The former Liverpool boss was present at the parade and had shared images on social media of the joyous scenes earlier in the day. But after news of the collision, thoughts quickly turned to those affected.
'My family and I are shocked and devastated, our thoughts and prayers are with all those who are injured and affected,' he wrote on Instagram. 'You'll never walk alone.'
Klopp, who ended a near nine-year spell in charge of the club last May, made his first return to the city over the weekend as the Reds lifted the Premier League trophy and enjoyed a parade denied of them in 2020 due to the Covid pandemic.
Reds legend Jamie Carragher also took to social media to extend his thoughts and sympathies to those affected by Monday's events.
'Devastating end to the day.........just pray everyone is ok,' he said alongside a picture of the iconic Liver Building in the city covered in red smoke from flares earlier in the day.
Meanwhile, shortly after the incident initially happened, Liverpool released a club statement offering their 'full support to the emergency services' dealing with the incident.
It read: 'We are in direct contact with Merseyside Police regarding the incident on Water Street which happened towards the end of the trophy parade earlier this evening.
'Our thoughts and prayers are with those who have been affected by this serious incident.
'We will continue to offer our full support to the emergency services and local authorities who are dealing with this incident'.
Liverpool icon Sir Kenny Dalglish had also expressed his shock and sadness at the incident.
'Shocked, horrified and deeply saddened about what happened at the end of the parade today,' he said.
'Our thoughts and prayers go out to everyone and their families who have been impacted by today's tragic event. Our anthem has never felt more appropriate, You'll Never Walk Alone. Your Liverpool family are behind you.'
Liverpool's local rivals Everton released the following statement: 'Our thoughts are with all those who have been affected by this serious incident in our city'.
Elsewhere, Manchester United's official account on the platform wrote: 'Our thoughts are with @LFC and the city of Liverpool after today's awful incident.'
A Premier League statement read: 'Everyone at the Premier League is shocked by the appalling events in Liverpool this evening, and our heartfelt thoughts go out to all those injured and affected.
'We have been in contact with Liverpool FC and have offered our full support following this serious incident.'
Authorities say both Prime Minister Keir Starmer and Home Secretary Yvette Cooper are being kept fully briefed on the developing situation.
Harry Rashid, 48, from Solihull, was at the parade with his wife and two young daughters when he witnessed the collision.
He said: 'It happened about 10 feet away from us. We were just in a crowd and we had no control over where we would be, because it was a very narrow street.
'The vehicle came to our right. It emerged from just right next to an ambulance, which was parked up.
'This grey people carrier just pulled up from the right and just rammed into all the people at the side of us.
'It was travelling south, down Water Street, straight towards this strand, which is where the docks are.
'It was extremely fast. Initially, we just heard the pop, pop, pop of people just being knocked off the bonnet of a car.'
PM Starmer added: 'The scenes in Liverpool are appalling — my thoughts are with all those injured or affected.
'I want to thank the police and emergency services for their swift and ongoing response to this shocking incident.
'I'm being kept updated on developments and ask that we give the police the space they need to investigate.'
The incident marred a day which was intended for celebration among Liverpool supporters after their club sealed a historic 20th league title.
The parade followed a 10-mile route. It started at Allerton Maze, heading north along Queens Drive in a similar route to the one used in 2019 - when the Reds won the Champions League.
There were a number of road closures due to the event, with Liverpool City Council strongly recommending that people did not drive.