Macedonian authorities have filed terrorism charges against five men in connection with the shooting deaths of five Macedonian fishermen in mid-April, Interior Minister Gordana Jankuloska said.

Two of those charged were still at large, while the other three were among 20 people identified as radical Islamists who were arrested in connection with the case Tuesday.

The killings of the fishermen near the Macedonian capital Skopje last month fueled tension in the Balkan country between majority Macedonians and the mostly Muslim ethnic Albanian minority.

State Prosecutor Ljupco Svrgovski told media Wednesday that if found guilty of terrorism, the suspects faced life imprisonment sentences.

The remaining 17 of those arrested during an early-morning raid on Tuesday were being interviewed by an investigative judge. They are being investigated on suspicion of terrorism, helping commit the murders and illegal possession and trade of weapons.

Jankuloska did not specify whether the suspects all belonged to the same ethnic group. She previously said most of them were Macedonian citizens.

About 800 police were involved in Tuesday's operation, called "Monster," raiding 26 houses around Skopje and seizing weapons, bulletproof vests and Islamic literature, police said.

Jankuloska said the 20 suspects arrested Tuesday were followers "of radical Islam, which is a danger not only for Christianity, but also for Muslims and others."

The ethnic Albanian coalition partner in the conservative government, the Democratic Union for Integration, or DUI, described the killing of the fishermen as "the biggest crime in the history of Macedonia."

DUI spokesman Bujar Osmani said his party "remains on the position that the killers are simply killers by name and surname, regardless of their ethnicity and nationality".

Tensions between Macedonians and ethnic Albanians have simmered since the end of an armed rebellion in 2001, when ethnic Albanian rebels fought Macedonian government forces for about eight months, seeking greater rights for their community. The conflict left 80 people dead and ended with the intervention of NATO troops.

Ethnic Albanians make up about a quarter of Macedonia's population of 2.1 million. Most Macedonians are Christian Orthodox.