Turkey has detained 10 retired admirals after they condemned Canal Istanbul, a project proposed by President Recep Tayyip Erdogan, for posing a possible threat to a pact regulating shipping through the country's key waterways.
The Ankara chief public prosecutor's office said on Monday that arrest warrants had been issued for 10 retired admirals, adding four other suspects were called to report to Ankara police within three days.
They are accused of "using force and violence to get rid of the constitutional order," NTV broadcaster said.
The arrest warrants came after 104 retired admirals said in a letter Saturday that opening the 1936 Montreux Convention up to debate was "worrying" and that the agreement "best protects Turkish interests."
The possibility of Turkey’s withdrawal from the pact that regulates shipping through the Bosphorus and Dardanelles straits linking the Mediterranean Sea to the Black Sea was raised after the approval last month of plans to develop a shipping canal to the north of Istanbul that would bypass the Bosphorus.
“Montreux provided Turkey the possibility to maintain its neutrality during World War II. We are of the opinion that there is a need to avoid any statements and actions that could cause the Montreux convention, an important treaty in terms of Turkey’s survival, to be brought up for discussion,” the group said.
The prosecutor launched an investigation into the retired admirals on suspicion of an "agreement to commit a crime against the state's security and constitutional order."
The letter drew condemnation from top government officials who claimed it appears to be a call for a coup.
"Stating one's thoughts is one thing, preparing a declaration evoking a coup is another," parliament speaker Mustafa Sentop said Sunday.
Presidential spokesman Ibrahim Kalin said the letter was "reminiscent of coup times."
"They should know that our esteemed nation and its representatives will never allow this mentality," he tweeted.
Coups are a sensitive matter in Turkey which has seen the military stage three putsches between 1960 and 1980.
There was also an abortive coup against Erdogan's government in 2016, which Ankara blamed on followers of US-based opposition cleric Fethullah Gulen in the military.
"Knowing and fully aware of the gains and losses under international agreements, the Turkish Armed Forces cannot be instrumentalized to serve the ambitions, greed and personal goals of individuals who have no official position or responsibilities," the defense ministry said Sunday.
Erdogan was expected to address the issue at a meeting later on Monday.