Police have named a man they urgently want to speak to over the murder of a man as he celebrated his 21st birthday.
Sam Cook, from Crosby, Merseyside, died in hospital after being stabbed in the basement area of the Empire bar and nightclub in Seel Street, Liverpool, just before midnight on Saturday October 21.
Detectives investigating his murder say 22-year-old Carl Madigan from Speke, Merseyside, may have vital information and are are asking him to come forward. They have warned the public not to approach him directly.
Det Chief Insp Mark Tivendale said: "Carl Madigan is someone we are very keen to speak to as soon as possible, as we continue our investigation into the tragic murder of Sam over three weeks ago.
"I would advise the public not to approach Madigan directly if you see him. Contact police on 999 immediately and allow us to take the necessary action.
"I also want to make it clear that having any current association with Madigan will bring police to your door, so I would encourage anyone with information to do the right thing and come forward as soon as possible.
"We are grateful to all those who have come forward so far in connection with Sam's murder, all of which is helping us progress the investigation."
Anyone with information on the whereabouts of Madigan is asked to contact detectives on the hotline number 0800 230 600, or alternatively contact Crimestoppers anonymously on 0800 555 111.
Mr Cook's family said last month he "always wanted to help people" and was "happy, caring and passionate about life".
They added: "We are thankful that in such a short life he accomplished so much, made so many friends and experienced the love and companionship of his girlfriend.
"But he was just 21, a young man with so much more to give. The memories of a happy, beautiful little boy kicking a ball about in the garden or tucking him safely into bed, seem like only yesterday."