Turkish police late Thursday arrested two officials of the Peoples' Equality and Democracy Party (DEM Party) for holding a so-called memorial service for a PKK terrorist at a DEM Party office in Istanbul.

Abdullah Arınan and Rojda Yılmaz, district chairs of DEM Party’s Esenyurt branch, were arrested on charges of "being a member of an armed terrorist organization" and "spreading terrorist propaganda."

The Chief Public Prosecutor's Office in Istanbul is still investigating the so-called commemoration ceremony held for PKK terrorist Gülşen Atalmış, who was eliminated in 1995.

Esenyurt, one of the country's biggest, with some 1 million residents, was the scene of another arrest last month where its district mayor, Ahmet Özer, a member of the main opposition’s Republican People's Party (CHP), was charged with having links to the PKK, blacklisted as a terror organization by Türkiye, the U.S. and the European Union.

Reports also said Özer was closely affiliated with the DEM Party before he was fielded as a candidate by the CHP in the latest municipal elections.

During local elections, the CHP had come under fire for "covertly" cooperating with the DEM Party, then known as the Peoples' Democratic Party (HDP). In the case of Esenyurt, both parties had agreed on Özer as a joint candidate, as the HDP refused to nominate a candidate for the district.

The DEM Party is known for its intricate links to the terrorist group and three of its own mayors were also sacked and replaced by government-appointed trustees earlier this month after they were convicted of membership in the PKK. The party subsequently launched protests in the southeast and its supporters confronted police in violent riots.

Several HDP mayors were removed from duty and replaced by trustees after the 2015 riots in southeastern regions. The party many times drew fire for transferring taxpayer money and funds to the PKK and for its mayors and local officials misusing funds in support of the PKK and providing jobs to the group’s sympathizers.

The arrests of opposition figures came amid increased debate around the end of terrorism and heightened security against PKK attacks in Türkiye after terrorists killed five in an attack on a Turkish aerospace firm in Ankara last month.