Arizona Tribune - Police, protesters clash outside maiden World Cup match in Mexico

Groups of teachers, relatives of Mexicans who have gone missing, and student activists gathered early Thursday outside the stadium amid a heavy police presence.

Some protesters breached barriers and exchanged blows with officers guarding the stadium's perimeter, moments after Mexico scored the tournament's first goal.

A handful of youths smashed vehicle windows with bats as police fired tear gas and dispatched mounted officers to corral the protesters, who scattered on foot.

Mexico's government has faced weeks of protests, mainly by teachers demanding better working conditions.

For a time it appeared the protests might prevent the city from staging an official World Cup fan zone in its famed Zocalo.

But thousands of fans poured into the plaza on Thursday, shoving and jostling their way through metal barriers, creating chaotic scenes shortly before kick-off in the opening game.

P.A.Mendoza--AT