Staff from one of Turkey's most respected opposition newspapers yesterday rejected as absurd "terror" charges against them on the first day of a trial which has intensified alarm over press freedom under President Recep Tayyip Erdogan.

The 17 defendants from the Cumhuriyet daily were detained from October last year and a dozen of them have now spent more than eight months in jail without being convicted of any crime.

They have been held under a state of emergency imposed after the July 2016 failed coup aimed at ousting Erdogan that the authorities blame on US-based preacher Fethullah Gulen.

The staff -- including writers, cartoonists and executives -- were applauded by supporters crammed into the Istanbul courtroom as the trial opened, an AFP journalist said.

Supporters released dozens of multicoloured balloons outside the courthouse, chanting: "Don't be silenced! A free media is a right!"

If convicted, the defendants face varying terms of up to 43 years in jail.

In an extraordinary coincidence, the trial opened on Turkey's annual national day of the press which marks the end of official censorship in the Ottoman Empire in 1908 under Sultan Abdulhamid II.

Those appearing in court included some of the best known names in Turkish journalism including the columnist Kadri Gursel, the paper's editor-in-chief Murat Sabuncu, cartoonist Musa Kart as well as its chairman Akin Atalay.

They are charged with supporting in the newspaper's writings three groups considered by Turkey as terror outfits -- the Kurdistan Workers' Party (PKK), the ultra-left Revolutionary People's Liberation Party-Front (DHKP-C) and Gulen's movement, which Ankara calls the Fethullah Terror Organisation (FETO).