It may have appeared odd that President Recep Tayyip Erdogan chose the 562nd anniversary of the conquest of Constantinople to castigate editors of a newspaper more than 8,000 kilometers (5,000 miles) away.

"There is a trash called The New York Times in the US. What are they saying? 'There are dark clouds over Turkey,'" Erdogan said, surrounded by an entourage of costumed Ottoman soldiers. "They wrote the same stuff about Abdulhamid in 1896," he said, referring to the last sultan to wield absolute power over the Ottoman Empire before being deposed.

In a response to the speech, US State Department spokeswoman Marie Harf wouldn't speculate whether the attacks were related to the election but did say that the US is "concerned about government interference in freedom of expression in Turkey."

Polls open Sunday

Turkey is a parliamentary republic, and its citizens head to the polls Sunday. And even though President Erdogan is not running, the election is in many ways a referendum on his expansion of authority.

Erdogan's former political party, the Justice and Development Party (AKP), needs to win 330 out of 550 seats in order to bring a new constitution to a popular referendum. Although recent polls show that as unlikely, Erdogan continues to campaign hard for his former party - despite his position's nominally apolitical role.

"The new constitution is the main theme in this election," Mustafa Sentop, an AKP lawmaker and the deputy in charge of election affairs, told a group of foreign journalists. "When Recep Tayyip Erdogan was elected president, he also mentioned that the existing system gave the president a large amount of authority."

Intrigue between former allies

Inside the country, it's been more than a mere war of words between the president and critical media. Criminal charges have already been brought against editors and reporters working for media linked to Erdogan's former ally, Fethullah Gulen, a US- based Islamic preacher whom the regime accuses of setting up a "parallel state" in order to bring down the government.

Dumanli was detained in December over a vendetta between Zaman's ownership and Erdogan

"It is obvious that anyone who disagrees with the government is declared an enemy of the state, and the government has used all its power and resources to make this happen," said Ekrem Dumanli, editor-in-chief of Zaman newspaper, who was detained in December and who is now prohibited from leaving Turkey while his case remains pending in court.

The Zaman newspaper, which has one of the highest circulations in the country, is controlled by the Gulen movement and has become editorially critical of the AKP and Erdogan personally since the exiled preacher and Turkish government parted ways about two years ago.

That ended a long alliance in which the Gulen-linked media championed a series of criminal prosecutions against a common enemy: Turkey's secular military elite, which had orchestrated coups and oppressed the country's religious underclass - and its political leaders - for decades.

Now, Erdogan and his allies accuse the Gulen movement of "terrorism" and conspiracy against the government, Dumanli said, but have yet to bring an indictment or formal evidence.

"They have accused us of many things, but there hasn't been any formal procedure in leveling these accusations," Dumanli said. "They often talk about a 'parallel structure' - but what law is that breaking? How is this even a crime?"

Editor faces life in prison

Even more serious charges have been brought against the editor of Cumhuriyet newspaper after it posted video evidence of Turkish trucks laden with arms and ammunition bound for Syria.

The newspaper had defied a media blackout of a January 2014 incident in which Turkish security forces discovered the weapons being smuggled in trucks. They were confronted by Turkish intelligence agents escorting the convoy, and the arms and materiel were allowed to cross the border.

Dundar faces life in prison for Cumhuriyet's dedicated reporting

A criminal complaint filed by Erdogan has asked for a life sentence plus an additional 42 years' imprisonment for Cumhuriyet's editor-in-chief, Can Dundar, for publishing the video footage on the paper's website.

The incident has been embarrassing for Turkey, raising questions about Ankara's support for armed opposition groups in Syria, especially those with ties to al Qaeda and the "Islamic State."

Last week, Turkish Prime Minister Ahmet Davutoglu said the contents were destined for ethnic Turkmens suffering from oppression at the hands of Syria's army.

"There is no account Turkey cannot give. Turkey has never supported terrorist organizations anywhere, anyhow," the prime minister insisted in the televised interview. "It does not have even a little stain on its record."

Soldiers and prosecutors involved in the search are now themselves facing prosecution, accused of being in league with Gulen's shadowy "parallel state."

The charges against the newspaper editor have brought swift condemnation by rights groups and press organizations in Turkey and abroad.

Erol Onderoglu, an Istanbul-based representative of the press freedom watchdog Reporters Without Borders, says Cumhuriyet is one of the country's oldest and most respected newspapers, and decidedly not the mouthpiece of an organization such as the Gulen movement.

"Everybody knows that Cundar is a very independent journalist of 30 years who has nothing to do with any religious community," Onderoglu told DW. "This reflects a very critical situation that probably will not end with the election."

No apologies

Going forward, Erdogan and his allies hope their theme of resisting outside interference will be well-received by voters. Taha Ozhan, chief adviser to Erdogan, wrote recently in the pro-government Daily Sabah newspaper that foreign criticism of his boss is counterproductive and stems from jealousy of Turkey's rising star.

"The coverage of Turkey in English-language media outlets, which is informed by public diplomacy and manipulations by the intelligence community," Ozhan wrote, "merely serves to sustain the global intellectual hegemony while engaging in character assassination of the country."

How well Erdogan's added pressure on the media will work in the ruling party's favor remains to be tested when polls open Sunday.