The suspects are accused of links with the Union of Kurdistan Communities (KCK), an organisation deemed by the authorities to be the urban wing of the outlawed Kurdistan Workers' Party (PKK).

"We will not yield to pressure," and "free press cannot be silenced!" shouted a group of demonstrators who gathered at the Istanbul court to protest the trial they deemed an attack against freedom of speech in Turkey.

Prosecutors accuse the 44 defendants of crimes including "membership in an armed organisation," which is punishable by up to 15 years in prison, according to the Anatolia news agency.

At least 12 of the suspects face up to 22 and a half years in prison on charges of "forming and running an armed organisation".

Monday's first hearing began more than three hours late partly because of the large crowd that forced the judge to vacate the room before the trial could start.

Tensions rose further when some lawyers demanded the right of the suspects to address the session in Kurdish, which is prohibited in Turkish courts.

"The Kurdish people and the Kurdish media are on trial today", said defense attorney Baran Isik, who accused the court of being "a tool" to silence government opponents.

"None of these journalists used weapons or glorified violence but they are prosecuted for membership in a terrorist organisation," said Ilhan Cihaner, lawmaker from the opposition Republican People's Party (CHP).

"It is not acceptable."

Monday's session is the third in a series of trials in which dozens of people, including lawyers, politicians and journalists, stand accused of similar crimes in Istanbul courts, where several related cases are pending.

The wider crackdown against the outlawed Kurdish rebels and their supporters began in 2009.

Since then, 700 people have been arrested pending trial over alleged links to the KCK, according to government figures, although critics say the true number arrested tops 3,500.

Ankara says the KCK wants to replace Turkish government institutions in Kurdish-majority southeastern Anatolia with its own political structures.

The PKK, listed as a terrorist organisation by Turkey and much of the international community, took up arms in the Kurdish-majority region in 1984, sparking a conflict that has claimed some 45,000 lives.