Mobile phone footage shows the moment teenager Coral Millerchip began kicking and hitting an 80-year-old man in Coventry city centre.
The video shows the man try to defend himself against the attack, but she kicks him and pushes him to the floor as friends cheer her on.
The man later died in hospital.
Millerchip, aged 19, was today jailed for a total of 44 months.
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A dry start, with sunny spells developing. However turning cloudier again later, with showers possible by the evening.
After a fine evening with some late sunshine to the end the day, a largely dry and fairly warm night will follow with clear spells.
Any remaining showers will fade, to leave it dry overnight.