LAHORE, Pakistan -- Sports-star-turned-politician Imran Khan was injured after he plunged from a forklift that was taking him up to a stage at a political rally just days before Pakistan’s parliamentary election.

A video of the fall showed Khan and three security guards standing precariously on the platform as it rose up, then suddenly toppling over at about 7 p.m. local time Tuesday (10 a.m. ET) at the rally in Lahore. Police estimate that Khan and his bodyguards fell from a height of 20-25 feet.

Athar Hussain / Reuters

Imran Khan, seen speaking to supporters in Karachi on Tuesday, was later injured in a fall at another political rally.

Khan, the chairman of the Pakistan Tehreek-e-Insaf party, was then taken to a local hospital for treatment.

"He fell, hit his head on the grill, and started bleeding. The chairman has been taken to a hospital, please pray for his health," said a message on Khan's Facebook page.

Thousands of well-wishers gathered outside Shaukat Khanum Hospital. Local police have ruled out foul play.

A doctor at the hospital said Khan is in stable condition and in good spirits. He suffered no internal injuries and his spinal chord is OK, but he did sustain a fracture in his back. He will be kept at least overnight. 

The May 11 election is being held amid tight security because of the risk of being attacked by the Pakistani Taliban.

Since April, the Pakistani Taliban have killed more than 70 people in attacks targeting three major political parties, preventing many of their most prominent candidates from openly campaigning, Reuters reported.

The Taliban say they are targeting "secular" parties and that elections only "serve the interests of infidels and enemies of Islam," the news service said.

However, they have mostly not attacked Khan's party, which advocates shooting down U.S. drones and withdrawing the Pakistani military from insurgency-infested Pashtun areas along the Afghan border, Reuters said. Right-wing religious parties that have joined the election race have also been largely left alone by the militants.

Khan made his name playing cricket, a hugely popular sport in Pakistan. He is regarded as one of the best players in the history of the game.

His political campaign has made great use of social media; his Facebook page currently has 822,000 likes.

NBC News' Ian Johnston and Reuters contributed to this report.

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