Canadian Prime Minister Justin Trudeau _ who's in a fight for reelection _ wore brownface while dressed as an "Aladdin" character at a 2001 event at the private school where he taught.
The photo came to light Wednesday evening, and the 47-year-old head of state admitted doing it and apologized.
"I shouldn't have done it. I should have known better, but I didn't," he told reporters while on a plane. "And I'm really sorry."
Zita Astravas, a spokesperson for the Liberal Party, confirmed to Time magazine, which broke the story Wednesday, that the image from the school party included Trudeau.
"It was a photo taken while he was teaching in Vancouver, at the school's annual dinner which had a costume theme of 'Arabian Nights,' " Astravas told the magazine.
Trudeau stopped teaching at the school after the spring of 2001.
A photo appeared in West Point Grey Academy's yearbook that year showing Trudeau in the costume as he stood with four women, none of whom appeared to have darkened their skin for the gala.
The image emerged in the dead heat of an election between Trudeau's Liberal Party and the opposition Conservative Party. Trudeau has also been nagged by a controversy involving claims he pressured his then-attorney general to drop corruption charges against a construction company.
Canada's election is set for Oct. 21.
