Two Turkish opposition mayors were removed from office, Ankara said Friday, after they were convicted of "terrorism" for belonging to the outlawed Kurdistan Workers' Party (PKK).

The pair are the fifth and sixth pro-Kurdish mayors to be dismissed on similar charges over the past two months, including the mayor of Istanbul's most populous district.

What do we know about the firings?

Tunceli's elected mayor Cevdet Konak, and Mustafa Sarigul, mayor of Ovacik in Tunceli province, in Turkey's southeast, were found guilty of membership in the PKK, which is classified as a terrorist organization by Ankara and its Western allies.

The PKK has waged a guerilla insurgency against the Turkish state since 1984, a conflict that has killed tens of thousands of people.

The pair were each given prison sentences of six years and three months this week, the interior ministry said, and replaced with state-appointed administrators.

Konakis is from the main pro-Kurdish Peoples' Equality and Democracy Party (DEM), which is often targeted by Turkish authorities for its alleged links to the PKK.

Sarigul is affiliated with the main opposition Republican People's Party (CHP), which caused a major upset for President Recep Tayyip Erdogan when it won local elections in March.

Both men told local media on Thursday that the accusations against them were unfounded.

Protesters clash with police over firings

The dismissals drew angry crowds in front of Tunceli city hall, where some tried to force their way through a police cordon, local media reported.

Konak's party condemned the firings, saying that "the government is slowly destroying the will of the people."

Among those previously ousted was Ahmet Ozer, the mayor of Istanbul's district of Esenyurt, who is a member of the CHP and is accused of having connections to the PKK.

Several other pro-Kurdish mayors have similarly been ousted from office following previous elections.

Erdogan's government has defended the sackings as part of efforts by Ankara to maintain security.

But opposition parties and rights groups say the moves are part of the president's goal of undermining democracy.

mm/zc (AP, AFP)