Turkish security forces detained at least 21 academics accused of signing a declaration calling for renewed efforts to end violence between government forces and Kurdish separatists, Turkish media reported on Friday.
The declaration criticized the Turkish government's handling of recent violence in the predominantly Kurdish southeast and called for the end of curfews. It also called on the government to "prepare the conditions for negotiations and create a road map that would lead to a lasting peace which includes the demands of the Kurdish political movement."
Prosecutors had launched an investigation into the declaration on Thursday after its signatories were heavily criticized by both President Tayyip Erdogan and Prime Minister Ahmet Davutoglu for supporting what they call terrorism.
The US Ambassador to Turkey, John Bass, said he was concerned about the investigations and detentions in a statement on the US Embassy in Ankara's Twitter feed.
Turkey has seen some of the worst violence for decades after the collapse of a ceasefire with the outlawed Kurdistan Workers' Party (PKK) last July left a peace process to end the three-decade insurgency in tatters.
The spiral of tit-for-tat violence has seen security forces carry out widespread operations in the southeast - locking down entire districts and pounding PKK outposts in residential areas, while Kurdish fighters have launched attacks against military and administrative targets. Hundreds have been killed in the fighting.
Overnight on Wednesday a Kurdish militant attack on a police station in Cinar killed six, including a baby, officials said.
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