Gunmen seriously wound policeman in Greece shooting

ATHENS (Reuters) - Gunmen linked to Greece's most militant guerrillas shot and seriously wounded a policeman in Athens on Monday, weeks after the killing of a teenager by police prompted the worst riots in decades.

Police said one of at least two weapons fired against a group of riot police guarding the Culture Ministry in the central Athens Exarchia district was the same used by the left-wing Revolutionary Struggle guerrilla group.

"The investigation into the 9mm weapon used in Monday's attack showed that it was used in an attack on a police station in April 2007," police said in a statement. That was the last attack claimed by the group which surfaced in 2003.

After the capture of the deadly November 17 leftist urban guerrilla group in 2002, Revolutionary Struggle emerged as Greece's most violent group with a series of bombings at ministries and police, and a spectacular rocket-propelled grenade attack against the U.S. embassy in Athens in January 2007.

Early on Monday, at least two assailants repeatedly fired semi-automatic weapons at riot police in the area where the 15-year-old was killed on December 6. Weeks of riots that followed the death caused damage worth hundreds of million of euros.

Police said the other weapon, an AK-47 assault rifle, was used in a December 23 attack on a police bus which a new leftist group, Public Action, said it staged to protest his killing.

"I express my abhorrence, my sorrow over the murderous attack against policemen," Prime Minister Costas Karamanlis told reporters after visiting the hospital. "Bullets against them are targeted mainly at democracy and society as a whole."

SERIOUS INJURIES

The gunmen fired about 40 shots tossed a hand grenade at police to cover their escape. A 21-year-old policeman was taken to hospital with serious injuries from three bullets.

"His condition is critical but stable ... This dramatic incident was a strike against democracy, against society and its institutions," Health Minister Dimitris Avramopoulos told reporters outside the hospital.

Police said they took in 72 people for questioning but no arrests have been made. The gunmen fled into the streets of Exarchia where the violence erupted last month. Police cordoned off the area and helicopters hovered overhead.

Tension remains high in the Greek capital which was hit by weeks of riots after the killing of Alexandros Grigoropoulos unleashed lingering anger at high youth unemployment and economic measures.

Political analysts said extremists were taking advantage of the explosive climate to stage their actions and provoke police.

"There are extremists who are ready to use such violence -- not just firebombs but to kill -- to keep the upheaval going," said Costas Ifantis, political science professor at Athens university. "The ground is fertile."

The violence has shaken a conservative government that has a fragile one-seat majority and trails the opposition in opinion polls by around six percentage points.

Political parties condemned Monday's attack, calling for a swift investigation and for the culprits to face justice.

(Writing by Dina Kyriakidou, Editing by Jon Boyle)