The chief prosecutor's office in the mostly Kurdish city of Diyarbakir opened the inquiry into HDP chairman, Selahattin Demirtas, on Thursday. The politician could face up to 24 years in jail if the case comes to court.
Dozens of people lost their lives in eastern Turkey last October, when clashes broke out between Turkish forces and Kurds protesting against Ankara’s refusal to help Syrian Kurds fighting ISIL terrorists in the northern Syrian border city of Kobani.
The news came only hours after Turkish President Recep Tayyip Erdogan verbally assaulted Demirtas, telling him to "know his place" and condemning his elder brother, Nurettin, over joining Kurdistan Workers’ Party (PKK) militants in the semi-autonomous northern part of Iraq.
"He would run there (too) if he found the opportunity," Erdogan said during a visit to China.
Demirtas has in return denied any wrongdoing and accused the Turkish president of targeting the HDP in revenge for upsetting the ruling Justice and Development Party (AKP) with a strong performance in the June 7 legislative elections.
"We have committed no unforgivable crimes. Our only crime was winning 13 percent of the vote,” he said at a parliament session on Tuesday.
On Thursday, Demirtas denounced as nothing more than a "show” Turkey’s alleged anti-terror police raids and its military campaign against ISIL Takfiri terrorists in Syria.
He accused Ankara of using purported anti-ISIL airstrikes as a "cover" to bomb PKK positions.
"A few air raids were launched by Turkey against ISIL targets for show only and it is over," Demirtas said, adding that most of the alleged suspects "were released”.
Turkey recently launched airstrikes against purported ISIL targets in Syria as well as PKK positions in Iraq, after a deadly bomb attack claimed by ISIL Takfiris left 32 people dead in the southwestern town of Suruc, across the border from Kobani.
Turkish police also launched a far-and-wide arrest campaign following the July 20 Suruc bombing. However, figures from the Turkish government state that only around one-tenth of those detained in police raids had links with ISIL, while the rest were Kurds.
A shaky ceasefire that had stood since 2013 was declared as null by PKK following the Turkish airstrikes against the group last week, narrowing chances of the two sides reaching a deal in the near future.
Ankara has been among the main supporters of Takfiri terrorists wreaking havoc on Syria since March 2011. The violence has reportedly claimed more than 230,000 lives up until now.
There are reports indicating that the Turkish government actively trains and arms the terrorists operating in Syria, and also facilitates the safe passage of would-be foreign terrorists into the crisis-stricken Arab country.