"The steps taken against the Turkish academics who signed a declaration regarding events in the southeast of Turkey are an extremely worrying development," an EU spokesperson on foreign affairs said in a statement.
"They are no longer detained, but the procedures against them are ongoing."
Turkish police yesterday detained at least 18 academics who signed a petition criticising a military crackdown in the southeast, triggering new alarm about freedom of expression in the country.
They were arrested in raids targeting 21 academics accused of disseminating "terrorist propaganda" by signing a petition denouncing military operations against Kurdish rebels.
More From This Section
The academics were questioned for a day before being released, Dogan reported late yesterday.
"While reaffirming our strongest condemnation of all forms of terrorist attacks, including by the PKK ... We restate that the fight against terrorism must fully respect obligations under international law, including human rights and humanitarian law", the EU spokesperson said.
"Freedom of expression must be upheld, in line with the Copenhagen political criteria; an intimidating climate goes against this.
Turkish prosecutors on Thursday launched a vast investigation into over 1,200 academics from 90 Turkish universities for engaging in "terrorist propaganda" and "inciting hatred and enmity" by signing the petition.
Entitled "We won't be a party to this crime", the petition urged Ankara to halt "its deliberate massacres and deportation of Kurdish and other peoples in the region", angering President Recep Tayyip Erdogan.