Greek police have foiled an imminent attack against a judicial target planned by a local terrorist group, Greek media reported on Saturday evening, adding that a counter-terrorism investigation is underway across the country.

Quoting police sources, Greek TV channels said that two suspects who were detained earlier on Saturday afternoon in a hideout in the central Athens district of Nea Smirni were leaving the place carrying weapons as if they were about to attack a target in the coming hours.

Reports claim that police confiscated three submachine guns, three AK-47 assault rifles, seven pistols, several rounds of ammunition, 200 grams (7 ounces) of TNT, four hand grenades and 50 kilograms (110 pounds) of ANFO, a powerful explosive mixture of ammonium nitrate and fuel oil widely used in improvised explosive devices, a police statement said.

“This is a case that the police have been following for some time now and the operation is still at its early stages,” said police spokesman Athanasios Kokalakis. “All I can tell you is that we have found weapons and they are being examined by experts to see if they have been used in (terrorist) attacks.”

Greek police are on alert these days for fear of violence ahead of Dec. 6, the second anniversary of the death of a teenager caused by police fire.

The death of Alexandros Grigoropoulos sparked the worst riots in Greece in four decades and ever since local guerrilla groups have stepped up attacks against police, judicial, journalistic and political targets.

In the garage of the building where the two suspects were apprehended, a large cache of weapons was found and confiscated, according to Greek media reports.

The result of ballistics tests expected on Sunday will reveal if the weapons are linked to two fatal attacks against a Greek policeman in June 2009 and a Greek journalist in July 2010.

“Revolutionary Sect,” which is connected to a series of hits since it first emerged in January 2009, had claimed responsibility for the two killings in statements released to Greek media over the past year, threatening more attacks in the future.

Apart from the two arrests at the hideout in Nea Smirni, counter-terrorism squads have raided at least a dozen other places over the past few hours and detained 10 suspects in the central Athens district of Exarchia, where Grigoropoulos was killed, and in the port of Piraeus and the northern city of Thessaloniki, according to media reports.

Police sources also said that the hideout in Nea Smirni is close to the home of one of the two young men arrested on Nov. 1 in Athens for the case of bomb parcels targeting foreign embassies and European leaders.

Sources: Reuters, Xinhua. Associated Press