Politician and former cricketer Imran Khan fell off a makeshift elevator and was injured during a rally for his election campaign. The incident happened during election campaigning in the eastern city of Lahore.
Khan and three others fell at least five metres as he was being lifted to a tall stage.
TV footage showed Khan being rushed towards a vehicle, blood covering his face and his eyes closed, apparently unconscious.
Reports later said Khan suffered spinal injuries but his condition was stable.
He was able to make a speech from his hospital bed, urging his supporters to vote on May 11.