ANKARA - Turkish prosecutors on Tuesday charged two opposition journalists with plotting a coup over a magazine cover criticising President Recep Tayyip Erdogan’s election win.

“Nokta editor-in-chief Cevheri Guven and managing editor Murat Capan were arrested on charges of attempting to overthrow the government by force,” the magazine wrote on Twitter. Police on Monday had raided the Istanbul offices of the left-wing Nokta and detained the two editors over the cover that read: “The start of civil war in Turkey”.

An Istanbul court later ordered that the magazine’s latest edition be withdrawn from the shelves, accusing it of inciting the public to commit a crime. Turkey launched new air strikes on Kurdish rebels and rounded up rivals of President Recep Tayyip Erdogan on Tuesday, an early hint of the hardline tactics his party intends to pursue after its surprise election win.

The West has voiced deep concerns about the vote Sunday that returned Erdogan's Justice and Development Party (AKP) to power, amid escalating fears that its landslide victory will lead to increasingly authoritarian rule in the Muslim-majority state.

Turkish prosecutors on Tuesday charged two opposition journalists with plotting a coup over a magazine cover criticising President Recep Tayyip Erdogan's election win, the magazine said.

"Nokta editor-in-chief Cevheri Guven and managing editor Murat Capan were arrested on charges of attempting to overthrow the government by force," the magazine wrote on Twitter. The military said its warplanes bombed bases of the outlawed Kurdistan Workers' Party (PKK) in southeastern Turkey and in their northern Iraq stronghold on Monday.

"Shelters, caves and arms depots identified as being used by terrorists from the separatist terrorist organisation were destroyed with air bombardments," it said in a statement.

Analysts say anxiety over the resurgent Kurdish conflict that has plagued Turkey for three decades and a spate of bloody attacks by the Islamic State group were key reasons why voters flocked back to the AKP. Ankara unleashed a new air war against PKK rebels after renewed militant violence in July, destroying a 2013 truce and hopes of fresh talks to end a conflict that has claimed 45,000 lives since 1984.

Deputy Prime Minister Yalcin Akdogan said conditions were not yet ripe to resume negotiations. "For us to say the peace process has started, the factors poisoning this process should be removed," he told NTV television.

A victorious Erdogan said Monday that Turks had voted for stability and unity and called on the entire world to respect the result.

The conservative Islamic-leaning AKP which has ruled single-handedly since 2002 won almost half of the vote, taking 315 seats and reclaiming the parliamentary majority it dramatically lost in June.

Critics warn that an emboldened Erdogan, who is seeking to expand his presidential powers, could become more autocratic and further polarise a country already deeply divided on political, sectarian and religious lines.

On Tuesday, police rounded up 35 suspects including top bureaucrats and police officers as part of a probe into supporters of a US-based cleric accused of plotting to bring down Erdogan.

Fetullah Gulen is charged with "running a terrorist group" which launched a widespread corruption probe into the president's inner circle in 2013, triggering a major purge of the police and the judiciary.

The action came only a day after the United States and two European observer missions expressed concern over the election campaign, particularly a crackdown on opposition media.

White House spokesman Josh Earnest said the US was "deeply concerned that media outlets and individual journalists critical of the government were subject to pressure and intimidation during the campaign".

"We have both publicly and privately raised our concerns about freedom of the press, freedom of speech and freedom of assembly in Turkey," he said.

"Unfortunately, the campaign for these elections was characterised by unfairness and, to a serious degree, fear," added Andreas Gross, head of the Parliamentary Assembly of the Council of Europe delegation.

But harassment of media continued Monday, with the arrest of the editor of Istanbul-based magazine Nokta over a cover story on Erdogan's win entitled: "The start of civil war in Turkey."

Ankara denied there was any pressure on the media, despite a string of high-profile arrests and raids on opposition television stations.

"Nobody is forced to be silent in this country," deputy premier Akdogan said, but added: "Press morality goes hand in hand with press freedom."

Erdogan, who became prime minister in 2003 and then Turkey's first directly elected president in 2014, was initially hailed in the West for transforming Turkey into a model of Muslim democracy and turning around its basket-case economy.

But a brutal police crackdown on nationwide protests in 2013 and concerns about democratic freedoms saw relations with the United States and the European Union cool.

"The AKP should take comfort in its large majority and start to view minority views and even peaceful dissent more benignly, in a way that befits a country negotiating accession to the European Union," said Sinan Ulgen of the Istanbul-based Centre for Economics and Foreign Policy Studies (Edam).

"The lesson of the two elections is clear: Turkey's voters want a strong, stable government, but not one that runs roughshod over its opponents," he said.