The protest movement - now in its fourth month - is the biggest in Chile since the return to democracy in 1990.

The government has promised some reforms, but the students say they do not go far enough.

Protest organisers said around 180,000 people took part in Thursday's march, making it the biggest in several weeks.

Some wore fancy dress or played musical instruments as they marched through Santiago.

As the march drew to a close, small groups wearing hoods threw stones at riot police, who responded with tear gas and water canon.

Student leaders are demanding wholesale reform Chile's education system, which they say is deeply unequal and desperately underfunded.

The system is sharply divided between private and public schools, an approach critics have labelled as "educational apartheid".

The protesters want the central government to take full control of education and increase spending on public schools.

They also want increased funding for universities, including scholarships rather than loans for poorer students, and an end to profit in education.

President Sebastian Pinera has responded by promising limited reforms and around $4 billion (£2.6 billion) in extra funding.

But he has categorically rejected calls for full state control and free education.

Mr Pinera addressed the issue again on Thursday in a speech to the UN General Assembly in New York.

His reforms promised "quality education for everyone, and free education for those who require it, so as to achieve the dream that no child be left out of higher education because of a lack of resources," he said.

But student leaders - many of them left-wing - say his proposed reforms do not address the fundamental problems of a system set up during the 1973-1990 military rule of Gen Augusto Pinochet.

"The people understand that the crisis in education is in fact a crisis of the model installed under the dictatorship. The protest is not against today's government, but against the neo-liberal model," student leader Camila Vallejo told the French news agency.