Turkish President Recep Tayyip Erdogan’s authoritarian crackdown on dissent from his war in Syria continued on Tuesday with the arrest of eleven members of the Turkish Medical Association (TTB), who dared to issue a public denunciation of the ironically-named “Operation Olive Branch.”

The TTB posted a statement on its website last week entitled “War Is a Matter of Public Health,” which said “No to war, peace now and everywhere!” and warned the assault on Syrian Kurds could cause “irreparable problems.”

“Any clash, any war, by paving the way to irrecoverable issues in terms of physical, spiritual, social and environmental health, will also bring a humanitarian drama,” the statement read.

The Erdogan government accused the TTB of publishing “propaganda in support of a terrorist organization and provoking the public.”

“Believe me, they are not intellectuals at all, they are a gang of slaves. They are the servants of imperialism,” Erdogan himself thundered at a meeting of his AKP Party on Sunday.

“This ‘No to war’ cry by this mob … is nothing other than the outburst of the betrayal in their souls. … This is real filth, this is the honorless stance that should be said ‘no’ to,” the Turkish president said. He flatly accused the organization of committing “treason.”

An Erdogan spokesman vowed that the authorities would pursue “those accused of deliberate disinformation” and warned the public to beware of “lying, fake, distortive, and provocative news, images, and gossip.”

Deputy Prime Minister Bekir Bozdag denounced the doctors’ statement as “shameful and unacceptable.”

Hurriyet Daily News reports that one of the doctors facing a detention warrant is the head of the organization, Rasit Tukel. The Turkish Health Ministry has filed suit to remove the dissenting members of the TTB from their posts, charging them with abusing their offices and committing a “hate speech” offense by criticizing the government.

“They do not represent Turkish doctors. The TTB has no right to make such a statement and it made a big mistake. There will be consequences for making such a statement at such a critical moment,” Turkish Health Minister Ahmet Demircan declared.

Erdogan-friendly Turkish newspaper Yeni Safak called for the TTB to be shuttered entirely, smearing the doctors as “terror-lovers.”

Amnesty International reports that the Ankara office of the Turkish Medical Association has “received a large number of threats of violence by email and phone calls, as well as on social media, which included anonymous threats that the office would be invaded.” Individual doctors were also called “traitors” and threatened with violence on social media.

After Erdogan’s fiery speech on Sunday, two trade unions aligned with the government called for a protest outside the Istanbul office of the TTB, prompting the organization to ask for police protection. Amnesty International repeated that call and said Turkish authorities should “provide immediate and effective protection for TTB’s members, staff, and offices.”

Members of the main Turkish opposition party, the Republican People’s Party (CHP), stood up for the Turkish Medical Association and criticized their detentions.

“You do not let doctors speak their minds. You oppress them,” CHP leader Kemal Kilicdaroglu said to the government at a party meeting on Monday. “They have called for democracy and peace but you round them up at dawn. Such actions will only undermine public support for the Afrin operation.”

Kilicdaroglu said the detentions are “not right” and will “only hurt Turkey’s image abroad.”