Canadian Prime Minister Justin Trudeau has been hit by gravel thrown by protesters during a campaign stop.

He was returning to his bus after visiting a brewery when he was struck by small stones. He was not injured. reports the BBC.

Trudeau called a snap election in mid-August, in the hope of gaining a majority government for his left-of-centre Liberal party. But his campaign has been disrupted by demonstrations against Covid-19 vaccine mandates and other restrictions.

Just over a week ago, the prime minister was forced to cancel an election rally after a crowd of angry protesters ambushed the event.

Speaking to journalists on his campaign plane after the incident in London, Ontario, Trudeau said he may have been hit on the shoulder and compared the incident to when a woman threw pumpkin seeds at him in 2016.