Open letter is harshly condemned by the president’s office, which says the move is ‘reminiscent of coup times’.
Turkish authorities on Monday detained 10 former admirals after a group of more than 100 retired senior navy officers issued a statement that government officials tied to Turkey’s history of military coups.
State-run Anadolu news agency said the retired admirals were detained as part of an investigation into their open letter, which was launched by the chief prosecutor in the capital, Ankara.
Prosecutors also ordered four other suspects to report to Ankara police within three days, opting not to detain them because of their age, the report said.
The former senior military leaders are accused of “using force and violence to get rid of the constitutional order”, NTV broadcaster reported.
The detentions come a day after the open letter signed by 104 retired admirals was sharply condemned by the presidential office, which said the move was “reminiscent of coup times” during Turkey’s past.
The 14 suspects are believed to have organised the declaration. Prosecutors launched a probe on Sunday into the former top navy officers on suspicion of an “agreement to commit a crime against the state’s security and constitutional order”.
Ankara’s approval last month of plans to develop a shipping canal in Istanbul, comparable to the Panama or Suez canals, opened up debate about the 1936 Montreux Convention.
Kanal Istanbul (Istanbul Canal) is the most ambitious of what President Recep Tayyip Erdogan calls his “crazy projects”, which have seen him building new airports, bridges, roads and tunnels during his 18 years in power.
In their letter released overnight on Saturday, the retired admirals said it was “worrying” to open the Montreux treaty up to debate, calling it an agreement that “best protects Turkish interests”.
The Montreux Convention guarantees the free passage through the Bosphorus and Dardanelles straits of civilian vessels in times of both peace and war. It also regulates the use of the straits by military vessels from non-Black Sea states.
The waterway between Europe and Asia through the two straits in Turkey is clogged with maritime traffic and has seen several shipping accidents in recent years.
“They [the admirals] should know that our esteemed nation and its representatives will never allow this mentality,” Presidential spokesman Ibrahim Kalin said on Twitter.
The Turkish defence ministry said the text had “no purpose other than undermining our democracy”.
The military, which has long seen itself as the guarantor of the country’s secular constitution, staged three coups between 1960 and 1980. In 2016, a failed coup led to more than 250 deaths.