Paramedics carry, an injured Australian tourist, to the ambulance after a shootout at the tourist area of Monastiraki in central Athens, July 16, 2014.[Photo/IC]

ATHENS - Greek police have arrested the leader of a local terrorist group during a shootout after a failed robbery attempt in central Athens that left four people slightly injured, according to police sources.

Fugitive terrorist Nikos Maziotis of the Revolutionary Struggle was injured during the shootout with policemen outside a jewelry store and a bank branch near the parliament building, preliminary information showed.

Among the injured was also a policeman and two tourists from Germany and Australia, police sources said.

Maziotis is said to have thrown a hand grenade during the shootout which did not go off.

As an official announcement is expected, the injured have been transferred to nearby hospitals, while a major operation is underway to trace and arrest his accomplices.

Eye witnesses said there was at least one more person involved in the robbery attempt.

Maziotis, a leading member of the Revolutionary Struggle which was active since 2003, has gone missing over the past two years during a leave from prison.

He had been arrested with his spouse who also went missing in July 2012 and is wanted for implication in terrorist acts.

Maziotis as well as fugitive convicted terrorist Christodoulos Xiros of the dismantled November 17 group who went missing January this year during a similar leave, have in recent months threatened with new attacks.

Revolutionary Struggle was linked to a long string of terrorist attacks against political, police, judicial and financial targets.

Among the group's major hits was the 2007 attack on the US embassy in Athens with a rocket-propelled grenade and most recently in April 2014 the car bomb blast outside the headquarters of the Central Bank of Greece in Athens. Both attacks caused material damages but no injuries, however the list of victims of domestic terrorist attacks in Greece over the past three decades is long.