Athens , Greece ( CNN ) -- Protesters and police clashed violently in front of the Greek parliament building Wednesday , as tens of thousands of demonstrators gathered in Athens on the first day of a two-day general strike over austerity measures . At least six protesters and 15 police officers were injured amid the disturbances , police said , and at least 15 people were arrested . Strikers in Greece aim to shut down wide sectors of the country , as lawmakers debate a new round of tough cost-cutting measures . Lawmakers passed the new austerity law in principal in an initial round of voting Wednesday , by 154 votes in favor to 141 against , with five lawmakers absent . Parliament must still vote on each article of the legislation Thursday before it can become law . `` Do n't bow your head , it 's time for resistance and struggle , '' marchers chanted in the capital earlier as they gathered for the union-backed demonstration . The violence broke out around lunchtime in one corner of the square , beside Parliament House , as a group of protesters dressed mostly in black threw rocks and Molotov cocktails at police . Officers fired tear gas and stun grenades , or `` flash bangs , '' in return , sending noisy detonations echoing round the square . Smoke filled the area by mid-afternoon as a fire burned in front of the finance ministry , forcing many peaceful demonstrators to move away . Police estimated that more than 70,000 people were protesting in Athens , and said they planned to put between 2,500 and 3,000 officers on the streets . Organizers estimated the turnout at 120,000 people . Initially , most of the protesters gathered peacefully in front of Parliament House waving union flags , red flags and banners . `` I 'm here for my children and everyone else 's children . Those punks in there have destroyed everyone 's lives , '' said former railway worker Diamandis Goufas , 62 , pointing at parliament . Greeks are angry at yet another round of planned austerity measures as Greece tries to bring down its stratospheric debt . Lawmakers are trying to cut government costs to reassure international backers it is doing enough to earn the bailout funds they have promised to pour into the country , with the latest austerity measures expected to pass Thursday . The new bill would lead to around 30,000 job losses and further cuts to wages and pensions for workers in the public sector . That has left at least some Greeks furious at the countries demanding that Greece bring down its spending . `` We are not lazy ; it 's the Germans , they want to take our blood , '' said Eleftherios Zarkados . At least one student said Wednesday that Thursday would not mark the end of the battle between politicians and the public . `` We will continue to resist even if the measures pass , '' said Sophia Titou , 21 , a law student who works at an oil refinery . Many on the streets say they are angry that the well-off people they believe are benefiting from corruption and tax evasion are not being pursued , while public sector workers pay the price for Greece 's woes . European Union leaders are scrambling to minimize the effect of Greece 's debt on their common currency , the euro . Over the weekend , finance ministers from the world 's largest economies pledged their commitment to take `` all necessary actions '' to stabilize markets . They aim to keep banks well capitalized so they can weather the effects of any defaults by Greece or other indebted countries like Portugal , Spain , Ireland or Italy . But there appears to be a split between France and Germany -- Europe 's two largest economies -- on how to do it . Germany has stressed that individual European states should inject capital into domestic banks that lack sufficient buffers . But analysts say France is opposed to this idea because it could jeopardize the nation 's top-tier credit rating . European leaders are expected to hear concrete details about how the plan might work at a European Council meeting Sunday . European Union heads of state are widely expected to finalize the plan in early November at a meeting of the Group of 20 world economic powers . CNN 's Andrew Carey , Diana Magnay and Ben Rooney contributed to this report .
NEW : Greek voters pass new austerity measures in an initial round of voting . At least six protesters and 15 police officers are injured in clashes , police say . They demand that Greece get its finances in order to get more EU money . European Union leaders worry that Greek debt threatens the EU .