Mr Trudeau's official photographer, Adam Scotti, tweeted a picture of the moment on Friday, captioning it: "Prom season in #Vancouver."
Here's how Twitter reacted:
@AdamScotti Love this photo bomb!— meredith brown (@rivermeredith) May 20, 2017
@AdamScotti Love Canada. PM can run through a crowd no crazy protective entourage necessary.— Wade Carter (@WadeCarter67) May 20, 2017
@AdamScotti What a fun surprise for this group of grads. :)— Destination BC (@HelloBC) May 21, 2017
"We were just taking photos and hanging around talking, and then Trudeau, he just comes running," one of the students in the picture, Constantine Maragos, tells CBC.
"At first, we were like, 'Why is the prime minister of Canada running the seawall? And then we started yelling for Trudeau to get in the photo."
The Canadian leader happily posed for this group picture:
Mr Scotti writes on Instagram that he has been documenting the Prime Minister's love for running as a side project. He posted three more hilarious pictures of the moment on Instagram:
"This is part of a little side project to document the places we go and the runs we go on. Sometimes it's just scenic shots, other times, it's running past an unsuspecting grad group - half clued in, others were more distracted by the ginger with the camera," he writes.
"A memorable moment for all. I always love to watch people's faces as they realise who just ran past, often several paces after he has passed." Click for more trending news
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