Greek police have used tear gas against students demonstrating against government plans to allow private universities.

Demonstrators tried to break through a barricade near the Greek parliament building on Wednesday, prompting police to fire the gas.

Another group of protesters threw firebombs at police motorcyclists.

A car belonging to the embassy of Bosnia-Herzegovina was set alight. Flames spread to four nearby vehicles and a shop, police said. No one was injured.

Firebombs outside Athens Polytechnic burned three police officers, after clashing with a group that took refuge inside the building.

Police units cannot enter the polytechnic under university asylum rules.

Further clashes between police and youths shut down one of Athens' main avenues.

Campaign

Greek student groups and academics have campaigned for weeks against the government’s plan to amend the constitution to permit the operation of private universities.

Demonstrations were also held in the cities of Patras and Iraklio, backed by unions of university professors, and primary and secondary education teachers.

Another rally was scheduled for the northern port city of Salonika later on Wednesday.

Greece's ruling conservatives and the opposition socialists agree in principle on the amendment, part of a wider overhaul of the constitution.

They assert that the move will improve the quality of university education in Greece.

Worker unions, student groups and left-wing parties disagree, arguing the state should instead devote more funds to public education.

The education amendment is to be voted upon in the spring, but the exact wording will be decided by the parliament elected after the next general election, scheduled for 2008.

PHOTO CAPTION

Protesters clash with riot policemen outside the Greek parliament in Athens January 17, 2007. (Reuters)