Trudeau jogged through a Vancouver prom on the seawall

Prime Minister Justin Trudeau was running along the Stanley Park Seawall on Fridaywhen he passed by a group of high school grads.

"We were just taking photos and hanging around talking, and then Trudeau, he just comes running," said student Constantine Maragos.

"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 PMobliged.

"We were stoked," Maragos said.

The graduatesaid some students were from Vancouver College, with several others from neighbouring high schools.

AdamScotti, photographer to the prime minister, also tweeted a photo of the run-in later in the evening.

(At first, based on Scotti's photo, CBC reported that the group didn't notice Trudeau. Students quickly contacted us through Facebook tolet us know they had, in fact, noticed.)

Last summer, Trudeau photobombed a Tofino wedding in similar fashion.

The prime ministerhas been out westthis weekreiterating his support for the Trans Mountain pipeline expansion, promoting Canadian techat a Microsoft summit and touting the Liberals'Canada Child Benefit program, among other things.

• Read moreon Trudeau'sstops in B.C., Alberta and Washington