Vancouver Police Inspector Laurence Rankin, who is heading the riot task force, said Wednesday thousands of tips made the arrest possible.
"Ultimately, it was the public that went to the website and were able to identify the suspect," Rankin said.
Jonathan Mahoney, 24, was arrested earlier in the day in Lanigan, Saskatchewan, where he was working in a potash mine, The (Vancouver) Province said.
Videos, photos and public tips made Mahoney a suspect in the assault of a man trying to stop looters at a department store. Fifteen people beat the man, who survived. Fourteen of the suspects have already been arrested.
Evidence placed Mahoney at the scene and his movements were tracked from Vancouver to Manitoba to his home province of Newfoundland and then to Saskatchewan.
He is charged with participating in a riot, assault, assault with a weapon and mischief.
The force said 872 charges have been filed against 275 people allegedly involved in the June 15, 2011, riot that caused $3.7 million in damage when the Vancouver Canucks lost the Stanley Cup final to the Boston Bruins, CTV News said.