Tyson Fury retires

World heavyweight champion Tyson Fury says he has retired from boxing in an expletive-laden message on Twitter.

The 28-year-old withdrew from a rematch with Ukrainian Wladimir Klitschko, scheduled for 29 October, because of reported mental health issues.

Fury, who holds the WBA and WBO titles, faces a hearing into a charge for an alleged doping violation in November.

"Boxing is the saddest thing I ever took part in" read his tweet, adding: "I'm the greatest, and also retired".