Chilean students protest in Santiago on Thursday as they press the government to reform education.

Story highlights

Students stage demonstrations at two schools in protest

Police fire tear gas and water cannons at a crowd of protesters

A stepped up police presence fuels anger among some students

Students have been protesting Chile´s education policies for months

CNN  — 

Students used chairs and desks to try to block police at the gates of a prestigious high school in Chile’s capital Friday.

Police fired tear gas and water cannon at protesters at the school, Liceo Jose Victorino Lastarria, which has been a flashpoint for recent student protests and sit-ins in the South American nation.

Since April, high school and university student demonstrators in Chile used marches, strikes and sit-ins to push for an overhaul of the country´s education system, protesting privatization and arguing that education should be more accessible.

Cristian Labbe, mayor of Providencia, the Santiago municipality where the school is located, ordered police to remove protesters from school sites Wednesday.

Classes began again Friday, with increased police presence inside school gates that fueled anger among some students and led to the clashes. There were also demonstrations at an all-girls school nearby, CNN Chile said.

Protesters have said they will not negotiate until government officials agree to conditions for dialogue that will not unfairly pressure students.

Labbe ordered an early end to the school year Friday for student protesters who had not already signed up for a government program aimed at making up for dozens of missed school days during the months of protests, CNN Chile reported.

But government documents indicate he may not have the authority to do so, CNN Chile said.