Turkish police took 14 academics into custody on Friday and were seeking to detain seven others over a petition which called for peace with Kurds in the south-east of the country, amid an uptick in violence.
The Dogan news agency reported that the academics in custody were from Kocaeli University, located in a province just east of Istanbul.
Chief Prosecutor Mustafa Kucuk accused the group of spreading terrorist propaganda and "insulting the moral integrity of the state.”
The petition - which was highly critical of Turkey's government and security forces, charging that they were carrying out a "massacre" - was launched this week as the country saw fighting between the armed Kurdistan Workers' Party (PKK) and the state intensify.
It has drawn the ire of the country's political leaders. President Recep Tayyip Erdogan has been launching regular verbal assaults on the academics, calling the petition "vile and barbaric" on Friday.
Prime Minister Ahmet Davutoglu implied the academics had chosen to "align" themselves with terrorists.
The petition initially launched with about 1,100 signatories but the number has since doubled, according to organizers.
Human rights groups have been critical of the strict round-the-clock curfews security forces are implementing in civilian neighbourhoods in the south-east. Kurdish officials say dozens of civilians have been killed.
Police also carried out raids against academics in other parts of the country, seizing computer equipment. At least two universities have meanwhile launched internal probes into their employees who signed.
The senate of Kocaeli University issued a scathing condemnation of the academics, accusing them of supporting terrorism by "ignoring the blood of the martyrs," referring to security forces killed.
Members of the largest opposition group in parliament, the People's Republican Party (CHP), however, were critical of the prosecutors, saying the criminal proceedings against the academics are "unlawful, not acceptable and extremely dangerous.”
The Turkish army says it has killed more than 370 alleged militants in just two districts in the south-east since it launched a fresh offensive last month.
The PKK, listed as a terrorist group in the US and EU, has been waging a 30-year battle with the state for greater rights and autonomy for the Kurdish minority in Turkey, which makes up at least 15 per cent of the country.
Kurds have complained of systemic discrimination for decades. The Kurdish language was banned for a number of years, though recently restrictions have been relaxed.