Rakeem Miles grabbed Samuel Winter from behind on Southwark Tube escalator. Miles ripped Winter's top and punched his head once. Winter collapsed with critical brain injury. Winter died two days later in hospital. Miles fled scene showing no remorse. No prior interaction between men on Jubilee Line train. Miles yelled abuse before attacking. Miles convicted of manslaughter after guilty plea. Cleared of murder charge. Sentenced to 8 years imprisonment. Added 5-year extended licence period. Eligible for parole after less than 5.5 years. Traced via Oyster card and arrested next morning. Winter was 28-year-old AI engineer and physiotherapist. Winter volunteered with charities. Family described Winter as gentle, kind, quick-witted, funny. Police emphasize zero tolerance for railway violence.