A man accused of stabbing a 21-year-old in the neck in an unprovoked and fatal attack is among nine "most wanted" suspects believed to have fled to the Netherlands.
Shane O'Brien, 28, is accused of walking up to Josh Hanson in the RE Bar in Hillingdon, west London, and killing him in front of his girlfriend in October 2015.
He is among nine fugitives, including another murder suspect, alleged drug smugglers and a convicted rapist, being hunted by British authorities.
Josh's mother Tracey said: "Every single waking moment we keep on trying our best to assist the police. We need justice for Josh. An incredible young man, a very hardworking young man, it's the least that can be done for him. It would give us the chance to grieve.
"It's soul-destroying at times. Mother's Day has just passed and Josh not being here was extremely painful for us. He was a wonderful young man, he was caring.
"Somebody out there has got to do the right thing. We need to grieve in peace and we have not been able to do that. Five months on, it feels like a lifetime already."
Addressing O'Brien directly, she said: "Come forward. Hand yourself in. You can't run forever. Stop our pain. Give answers."
O'Brien, who is from London and also uses the first name Troy, is white, slim, 6ft with grey eyes and short, dark brown hair. He has a birthmark on his face and a tattoo that says Shannon 15-04-06 on his back.
The other murder suspect being hunted by UK authorities is David Ungi, from Liverpool, who is accused of killing Vinny Waddington, 18, in the Garston area of the city in July 2015.
It is claimed that the 24-year-old, with two other men, used a car to ram a motorbike before fatally shooting pillion passenger Mr Waddington and injuring the driver Francis Humphries.
The rogues' gallery - put together by Crimestoppers and the National Crime Agency (NCA) - also includes accused "drug dealer" Shazad Ghafoor, 29, who allegedly stole a courtesy car from a Land Rover dealership in Manchester in August 2013 using a false name, sparking a high-speed police chase with his wife and children in the car.
The dramatic pursuit ended with him rolling the car in Halifax, West Yorkshire, and police found up to £100,000 in cash stashed in the vehicle.
He is accused of a string of offences for the chase, along with two counts of dealing cannabis for massive hauls that were allegedly found in a car in Withington and a house in Burnage, both in Manchester.
Crimestoppers chairman Lord Ashcroft said: "With the support of the Dutch authorities and the public, we are confident that we can successfully hunt these people down."
The most wanted list also includes suspected drug smuggler David John Walley, 40, who is alleged to have smuggled MDMA and cocaine into the UK in parcels delivered to Manchester; and Ahmed Dervish Omer, 45, from Nottingham, who fled in the middle of his trial in November last year but was found guilty in his absence and sentenced to 10 years for drug dealing.
Dave Allen, from the NCA, said: "Those who believe they can use the Netherlands to evade capture or continue illegal activities soon find out that it is not a safe haven."
The remaining suspects include Michael Paul Moogan and Robert Stephen Gerrard, both 52 and from Liverpool, who are accused of being part of an international drug trafficking ring; and Mark Liscott, 55, from Great Barr, Birmingham, who is wanted for allegedly dealing class A and B drugs while out on licence for a jail term for dealing cannabis.
Convicted rapist Rezgar Zengana, 33, is also on the list for posing as a minicab driver in Glasgow in December 2006, and picking up a 25-year-old woman who he attacked. He was convicted for rape but has yet to be sentenced.
Anyone with information can call Crimestoppers anonymously on 0800 555 111.