Turkey's most government-critical newspaper has, almost overnight, made an about-face, joining scores of other media outlets that toe the government's line, as two prominent opposition journalists go on trial, facing life imprisonment on charges related to their reports of an alleged government arms shipment to Syrian rebels.

The authorities' seizure of Zaman newspaper and its sister outlets and the trial that starts Friday of Cumhuriyet newspaper's editor-in-chief, Can Dundar, and its Ankara representative, Erdem Gul, are the latest steps in the government's increasingly bold moves to curb media freedoms, including the firing of journalists, the exertion of financial pressure on media groups and the censoring of websites.

The developments are another worrying sign that the country, which just a few years back was hailed as a model Muslim democracy, is becoming one where dissenting views are suppressed and the media is gradually being placed under government control.

On Thursday, dozens of writers including Nobel laureates, addressed an open letter to Prime Minister Ahmet Davutoglu, saying Turkey must drop charges against the Cumhuriyet journalists and end its crackdown on free expression.

"We, the undersigned, are extremely concerned about the increasing climate of fear and censorship and the stifling of critical voices in Turkey," said the letter published by PEN International, an organization which promotes literature and freedom of expression around the world.

"We believe that Can Dundar and Erdem Gul are facing life in prison simply for carrying out their legitimate work as journalists," they said.

The group also expressed concern over the "increasing climate of fear and censorship and the stifling of critical voices in Turkey."

But the country's allies have been silent for the most part on the issue.

Turkey, a NATO country that aspires to be a member of the European Union, is a key ally in addressing the conflict in Syria and the migrant crisis that has spilled into Europe. Critics say Turkey's strategic importance has forced allies to keep mum on the government's moves to curb the country's once-vibrant and diverse media.

Police this month used tear gas and water cannons to force their way into Zaman's headquarters and enforce a court decision to appoint trustees to oversee the papers' management. The papers' chief editors were sacked and replaced, turning it into yet another outlet that all but serves as a mouthpiece for the ruling Justice and Development Party, or AKP, which was founded by President Recep Tayyip Erdogan.

"The newspaper that's now being sold at newsstands has nothing to do with the newspaper that I or my colleagues had envisioned," Ali Colak, the former arts and culture editor at Zaman newspaper, told The Associated Press.

Zaman is linked to a religious movement led by U.S.-based Muslim cleric Fethullah Gulen — who once supported Erdogan, but is now his chief foe. Zaman's takeover is part of a government crackdown that has also affected the judiciary and police, as well as the wider campaign to silence opposition media.

"There are very few critical media outlets right now," said Asli Tunc, professor at Bilgi University's Faculty of Communication. "And that space is shrinking every day."

For those that remain, there's a chilling effect. "They are afraid that the next victim will be them," Tunc said.

Since the AKP's rise to power in 2002, several news outlets seized by the government have been handed over to businesses close to the party. Tax inspections and tax fines have served to intimidate many media outlets which fear falling foul of the government. Journalists who are critical of the government have been fired. More than a dozen journalists are in prison, although the government insists they have been jailed for criminal activity, not journalistic work.

Last year, a group of Justice party supporters raided the headquarters of Hurriyet newspaper, following criticism by Erdogan. Soon after, Hurriyet columnist Ahmet Hakan was chased and beaten.

Turkey frequently blocks access to Websites and a pro-Kurdish television was recently taken off the air. Foreign journalists have been arrested and deported for reporting on Turkey's renewed conflict with the Kurdistan Workers' Party, or PKK, in the country's mostly-Kurdish southeast region. German publication Der Spiegel's Istanbul correspondent Hasnain Kazim was forced to leave Turkey this month after his accreditation was not renewed following reports critical of the government.

Kazim wrote in Spiegel Online that he "made an effort to reflect events critically and fairly" in his reporting. "Yet, just like many other journalists, I learned the president and his supporters are allergic to any form of criticism," he said.

According to Reporters Without Borders, Turkey ranks 149th out of 180 countries in its press freedoms index. This week, the Committee to Protect Journalists launched what it called a "Turkey Crackdown Chronicle," documenting media freedom abuses in the country.

"In recent weeks in particular, the sheer number of media outlets left out there that are critical or independent is shrinking with the speed of light," CPJ Europe and Central Asia Program Coordinator Nina Ognianova told the AP.

Prime Minister Ahmet Davutoglu rejects accusations that Turkey is stifling free press.

"Freedom of expression ... is a red line for me and our party," he said in January. "I do not expect any limitation and restriction on freedom of expression. Everyone is free to express their views."

Cumhuriyet's Dundar and Gul were detained in November after Erdogan himself filed a complaint against the two, accusing them of spying for their May reports that featured images of what it said were Turkish trucks carrying ammunition to Syrian militants. The images reportedly date back to January 2014 when local authorities searched Syria-bound trucks, touching off a standoff with Turkish intelligence officials. The paper said the images proved that Turkey was smuggling arms to rebels.

The government initially denied the trucks were carrying arms, maintaining that the cargo consisted of humanitarian aid. Some officials later suggested the trucks were carrying arms or ammunition to Turkmen groups in Syria.

Andrew Gardner, Turkey researcher for Amnesty International, said the trial should not be taking place. "You should never prosecute journalists for working on a story that is in the public interest," he said, questioning whether the two could receive a fair trial.

Dundar told reporters the trial aims to intimidate other journalists.

"While punishing us, what they really try to achieve is to silence others," Dundar said. "It's blind-folding and intimidating."

Three academics, meanwhile, were jailed last week pending prosecution for allegedly making terrorist propaganda for signing a declaration that called on the government to end military operations against the Kurdish rebels.

The country's justice minister said as many as 1,845 cases have been opened against people accused of insulting Erdogan under a previously seldom-used law. Critics say Erdogan has been aggressively using the law to muzzle dissent. Those who have gone on trial include celebrities, journalists and students — many for their postings on social media.


Associated Press Writers Dominique Soguel and Neyran Elden in Istanbul contributed.