ATHENS (AFP) - Greek youths hurled Molotov cocktails and pelted shops with stones Monday during violent protests in Athens to mark the second anniversary of the killing of a 15-year-old boy who was shot dead by police. A group of around 100 hooded students hurled stones at windows of banks and shops in the centre of the Greek capital and set fire to rubbish bins as they marched towards the parliament building to commemorate the death of Alexis Grigoropoulos. At one stage, a group of protestors threw a Molotov cocktail at a luxury hotel near the parliament and stoned a nearby police cordon before riot squad officers moved in. Police dispersed the protestors by firing tear gas, and one male protestor sustained a minor head injury when he was hit by a projectile, witnesses said. Most of the demonstrators marched peacefully towards the parliament building, chanting Greece is not a protectorate and waving banners proclaiming IMF (International Monetary Fund) out. They were railing against the oversight imposed on the country by the European Union and the International Monetary Fund in exchange for a 110-billion-euro (148-billion-dollar) loan that saved it from bankruptcy earlier this year. IMF chief Dominque Strauss-Kahn is due to visit Greece on Tuesday, where he will meet leaders and address parliament. Some 5,000 police personnel were on alert and central Athens was restricted to public transport for a day of demonstrations called by students, labour unions and leftist groups to commemorate Grigoropouloss death, a police official said. Greek Minister for Citizen Protection Christos Papoutsis told the daily Ta Nea that the tight security measures were imposed to ensure the safety of citizens and their right to express themselves. Grigoropoulos killing during a December 2008 night patrol in the Athens district of Exarchia sparked days of urban unrest across Greece, with initial anger at the police compounded by the countrys worsening economic situation. In October, a court in the town of Amfissa convicted policeman Epaminondas Korkoneas of culpable homicide and sentenced him to life in prison for the slaying. The trial was held under heavy police guard after a far-left extremist group threatened to kill Korkoneas, prompting authorities to relocate the trial from Athens to Amfissa, 200 kilometres (125 miles) northwest of capital. Two of the suspects were already wanted by police in connection with a radical anarchist group, Conspiracy of Fire Nuclei, that was behind a parcel bomb campaign against European leaders and embassies uncovered last month.