Turkish prosecutors launched Monday a probe into the main opposition party chief after he called President Recep Tayyip Erdogan a "tinpot dictator," AFP reported.
Kemal Kilicdaroglu, head of the Republican People's Party (CHP) was speaking out against the recent arrests of Turkish academics who signed a petition against Turkey's military crackdown against Kurds in the southeast.
"Academics who express their opinion are being detained, one by one, because of a tinpot dictator," Kilicdaroglu said during a CHP meeting this weekend.
"How dare you (Erdogan) send police to these peoples' doors and have them detained," Kilicdaroglu said. "Tell us, tinpot dictator, what do honor and pride mean to you?"
The chief prosecutor in Ankara launched the investigation on charges of "openly insulting the president," state-owned Anadolu news agency reported. The crime is punishable by up to four years in prison.
Erdogan has separately filed a civil lawsuit against Kilicdaroglu, seeking $33,000 for "slander."
In recent months, concerns have grown over deteriorating freedom of expression in Turkey, especially the mounting numbers of people arrested for "insulting" Erdogan.
On Friday Turkey arrested at least 21 signatories to the academic petition denouncing Turkey's all-out offensive in Kurdish cities, which activists claim has killed dozens of civilians.