Fans spotted former prime minister Justin Trudeau enjoying fittingly prime seats to Katy Perry’s Montreal concert in photos and videos posted to social media.

If you were at the Katy Perry concert in Montreal, there's a chance you heard former Prime Minister Justin Trudeau "Roar" among the crowd.

It all kicked off Wednesday night at the Bell Centre in Montreal, where Perry brought down the house with her new tour. Among the 21,000 fans in attendance was none other than 53-year-old Trudeau, glowing and grooving alongside his 16-year-old daughter, Ella-Grace.