Pakistan's former PM Imran Khan has been shot and wounded during a protest march in the eastern city of Wazirabad, in an apparent assassination attempt.

Members of his PTI party said another four people were hurt on Thursday - but no-one was killed. Mr Khan, 70, was leading the march on the capital Islamabad to demand snap elections.

 It was not clear whether he had been hit in the foot or leg, but an aide was quoted as saying he was not in danger.

Unidentified assailants opened fire on a container-mounted-truck carrying former Pakistan prime minister Imran Khan at Wazirabad in the country's Punjab province.

According to local reports, Khan and some leaders of his Pakistan Tehreek-e-Insaf (PTI), including senator Faisal Javed Khan, suffered injuries in the firing.

Khan was shot in his foot at the rally. Khan was then lifted and taken in a car to a safe location. He was rushed to a hospital where doctors said he was out of danger.

"He is in a stable condition," Raoof Hasan, a senior Khan aide was quoted as saying by . "This was an attempt to kill him, to assassinate him," he added.

"Khan is being taken to Lahore by road. He is not critical but he received a bullet injury," Umar said, adding that Khan's opponent couldn’t see Pakistan being transformed.

Prime Minister Shehbaz Sharif condemned the shooting and ordered the interior ministry to conduct an investigation immediately.