Voting has begun in Greece's general election, with opinion polls indicating a tight race between the left-wing incumbent Syriza party and the conservative New Democracy.<br />The snap election, Greece's fifth in six years, was called after Syriza lost its parliamentary majority in August.<br />Syriza leader Alexis Tsipras's popularity plummeted after he agreed a new bailout deal with European leaders.<br />The bailout involved austerity measures which Syriza had vowed to oppose.<br />Greece is mired in a deep financial crisis and whoever wins Sunday's election will have to oversee further tough economic reforms.