The Greek Prime Minister, Antonis Samaras, has issued a plea for calm in a speech, amid protests on the streets of Greece.
Samaras vowed not to let violence stop Greece achieving "growth" and "prosperity" on Thursday.
He said that the country is close to "economic rebirth" after years of recession.
Tensions have been building on the streets of Athens after an anti-racism rapper was killed by a supporter of far-right group Golden Dawn on Tuesday night.
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Thousands have protested on the spot where Pavlos Fissas, 35, was stabbed to death in Athens, and protests have been reported in Patras and Thessaloniki, two other Greek cities. Further protests are expected Thursday evening.
Samaras described the murder as "inhuman".
Earlier on Thursday, Yannis Stournaras, the Greek finance minister, told a conference that the economy was heading towards recovery, after six years of recession.
(Read more: Could tourism give Greek economy much-needed boost?)
There are also concerns that Greece might need a third bailout. The IMF estimates that Greece will need an extra 10-11 billion euros ($13.4-$14.7 billion) in aid in 2014-2015.