Egypt's chief prosecutor referred 20 journalists from the al-Jazeera TV network for trial.

They face charges of joining or assisting a terrorist group and spreading false news that endangered national security.

It was the first time the Egyptian authorities tried journalists on terror-related charges.

Prosecutors have depicted the Qatar-based al-Jazeera network as biased toward ex-president Mohammed Morsi and the Muslim Brotherhood.

Al-Jazeera denies bias and has demanded the release of its reporters, whose arrest sparked outcry from civil rights and journalist protection groups.

The prosecutor's office said 16 Egyptians in the case are accused of joining a terrorist group, while four foreigners - an Australian, a Dutch citizen and two Britons - are accused of helping promote false news.

Prosecutors claimed that the accused had established a media network of 20 people who used two suites in a luxurious hotel in Cairo as a media centre, supported with cameras, broadcasting equipment and computers.

The statement said the defendants "manipulated pictures" to create "unreal scenes to give the impression to the outside world that there is a civil war that threatens to bring down the state."

Al-Jazeera's reporters in Cairo had been operating out of a hotel room after repeated raids on the network's Cairo office.

The prosecutors' statement said eight of the defendants were in custody, including the three journalists arrested in December - two Egyptians and an Australian. It was not made clear who the other five were.

The only other two Al-Jazeera reporters known to be in custody were arrested in August while covering a police crackdown on pro-Morsi protesters in Cairo that left hundreds dead.

Arab Network for Human Rights Information spokesman Gamal Eid said: "It is a state of hysteria that has reached the extent of making up charges."

He added that among the various agencies of the state each was "practicing its repression its own way ... We have repressive republics operating in one nation."

"This is an insult to the law," he said. "There is no evidence in the case."