Chile's foreign minister filed a formal complaint with Ottawa over what he called "unjustified aggression" by Toronto police as they scuffled with Chilean team members after a FIFA Under-20 World Cup soccer match.

The incident took place late Thursday after the team lost 3-0 to Argentina in a semifinal match at BMO Field in Toronto. According to a Chilean official, police used pepper spray and Tasered some players in order to prevent them from reaching a large fence that separated them from hundreds of angry, chanting fans.

Chilean President Michelle Bachelet said the reports of police using pepper spray and batons were "serious facts."

"In our opinion, what happened is particularly serious because the Chilean delegation suffered an unjustified use of force," Bachelet said.

On Friday morning, Chilean Foreign Minister Alejandro Foxley confirmed he sent a letter to his Canadian counterpart, Foreign Minister Peter MacKay, demanding the Canadian government explain why law enforcement officers reacted with what he described as such "unusual methods."

"You can't treat people who have gone there to represent Chile in a sporting event like this," said Foxley.

"Above all, we decided to send a diplomatic note … to make them understand the malaise in Chile over what happened, the excessive violence, and to formally ask them to give us a detailed explanation of why this happened and who is responsible."

A spokesman for Foreign Affairs in Ottawa, André Lamay, said later in the day that MacKay would not comment on the incident until Ottawa receives the official letter of complaint.

Prime Minister Stephen Harper, who was warmly received in Chile just days ago, was hesitant to say much about the incident.

"As we know, these international soccer matches are hotly contested and often become very emotional," Harper said in Port-au-Prince, Haiti. "Look, as you know, there are processes in Canada by which the authorities review these kinds of incidents."

When the brawl took place, tempers were already simmering because the team felt the officiating unfairly affected the outcome of the game.

Police eventually handcuffed several players, some of them bloodied and screaming, and escorted them back into the dressing room while shocked FIFA and Canadian soccer officials looked on.

Toronto Police Chief Bill Blair issued a statement defending his force.

"The job of my officers was to respond in a firm, but fair, manner to end that violence. They are trained to do so, and that is what they did," he said.

None of the players were charged.