Athens - Hundreds of demonstrators battled rain on Thursday to march through the Greek capital and cities across the country against the conservative government's reforms and the recent police shooting of a teenager.

All flights to and from Athens' International Airport were halted for several hours due to a strike by air traffic controllers demanding a pay rise and greater job protection.

Airport employees were joined by civil service trade unions and students who rallied through Athens.

The strike follows days of riots across Greece sparked by the shooting of 15-year-old Alexandros Grigoropoulos by police on December 6. The policemen accused of the shooting have been detained and charged with manslaughter.

More than 100 people have been injured and about 400 have been detained during the protests while hundreds of shops and banks have been firebombed, vandalised and looted in the uprisings.

Reports said another teenager was injured in a shooting Thursday. The details of the shooting were not immediately clear but the boy was being treated in an Athens hospital and was out of danger.

Students have called for solidarity rallies across Europe.

On Wednesday, protesters hung two giant banners from the ancient Acropolis with the words "resistance" in five different languages.

Across the country students refrained from attending classes at hundreds of secondary schools and universities, saying they were under occupation.

The demonstrations have spread to other European countries and many policymakers have expressed concern that they might get out of control as unemployment rises due to the recent financial crisis.

The unrest has unsettled the conservative government, which has a one-seat majority and trails in opinion polls. Conservative Prime Minister Costas Karamanlis has rejected calls to step down, despite growing public pressure.

Earlier this week he acknowledged some of the problems that had fuelled the anger of young people.

In a speech to parliamentary colleagues on Tuesday, he said "long-unresolved problems, such as corruption in everyday life and a sense of social injustice disappoint young people." (dpa)