A man has been jailed for a "horrific" attack which left his victim with brain injuries and a fractured skull.
Christopher Subham, 38, attacked a 41-year-old man on Bishopsgate Street near Leeds railway station after an argument on 12 August.
Leeds Crown Court heard how Subham, of no fixed address, struck the man over the head with a large plank of wood with exposed nails in it.
He admitted grievous bodily harm with intent and was jailed for 10 years.
He had previously denied the charge but, appearing via videolink from HMP Leeds, changed his plea to guilty.
Subham was also sentenced to an extended licence of four years on release.
Det Con Ian Grice from British Transport Police said: "This was a horrific and despicable act of pre-meditated violence.
"Subham purposefully strode up to his victim, who was sitting in a doorway, and without any hesitation smashed him over the head with the piece of wood with the nails exposed.
"His family must now deal with the ongoing recovery of their son from his horrendous injuries."

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