CAIRO - Egyptian prosecutors Wednesday referred to trial 20 journalists working for Al-Jazeera television, including four foreigners accused of "airing false news."
The Qatar-based news channel, which has incensed Egypt's new military-installed authorities with its coverage of their crackdown on the Muslim Brotherhood, said the charges are baseless and "silly."
And Amnesty International called the move a "major setback for media freedom in Egypt" designed to stifle independent news coverage.
The 16 Egyptians have been charged with belonging to a "terrorist organisation... and harming national unity and social peace," a prosecution statement said.
And two Britons, an Australian and a Dutch woman have been accused of "collaborating with the Egyptians by providing them with money, equipment, information... and airing false news aimed at informing the outside world that the country was witnessing a civil war."
Of the 20, only eight are in detention, while the others are being sought, the prosecution said.
The network said only five of its journalists are being held.
The prosecution did not name those held, but three Al-Jazeera journalists were arrested on December 29. They are Peter Greste, an acclaimed Australian who formerly worked for the BBC; Canadian-Egyptian Mohamed Adel Fahmy and Egyptian producer Baher Mohamed.
Al-Jazeera said "the entire world knows that these charges against our journalists have no basis."
They are "silly charges and not based on any reality," the channel said.
"This is a challenge to freedom of speech and the right of journalists to report different aspects of events, and the right of the people to know what is happening," it added, vowing to pursue the case "all the way."
London-based Amnesty International demanded the immediate and unconditional release of Greste, Fahmy and Mohamed.
Its secretary general, Sail Shetty, said the prosecution "sends the chilling message that only one narrative is acceptable in Egypt today -- that which is sanctioned by the Egyptian authorities."
"Journalists cannot operate freely in a climate of fear. The latest development is a brazen attempt to stifle independent reporting from Egypt. In the lead-up to elections, a free press is essential."
A constitution drafted by the interim authorities was adopted earlier this month, and presidential and parliamentary elections are due to be held later this year.
The prosecution had previously accused the Al-Jazeera crew of links to the Muslim Brotherhood, which has been blacklisted by the authorities as a terrorist group.
That is part of what has been a deadly government crackdown on the Brotherhood since the July ouster of president Mohamed Morsi, who hails from the movement.
The blacklisting makes promotion of the Brotherhood, either verbally or in writing, punishable by lengthy prison sentences.