Three Al-Jazeera journalists were back in court Thursday over their alleged links with the blacklisted Muslim Brotherhood, with Amnesty International denouncing their detention of more than 100 days. The hearing is the fifth in a trial which has sparked an international outcry and fuelled fears of a media crackdown by the military-installed authorities since the army deposed Islamist president Mohamed Morsi in July. The authorities have been incensed by Qatar-based Al-Jazeera's coverage of their crackdown on Morsi supporters which, according to Amnesty, has seen more than 1,400 people killed and thousands jailed. In the last hearing on March 31, the court rejected a bail plea by Australian journalist Peter Greste, Canadian-Egyptian Mohamed Fadel Fahmy, the Cairo bureau chief of Al-Jazeera English, and producer Baher Mohamed. The three men, who stand accused along with 17 other defendants, have been detained for more than 100 days. Amnesty International in a Wednesday statement said the three journalists were "prisoners of conscience" and called for their immediate and unconditional release. "What the Egyptian authorities are doing is vindicative persecution of journalists for merely doing their jobs," the statement said, In the trial, 16 Egyptian defendants have been charged with belonging to a "terrorist organisation" and four foreigners are 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 defendants, eight are in detention and the others are being sought. The family of another Al-Jazeera journalist, Abdullah Elshamy, called on Tuesday for his immediate release, saying that his health has deteriorated during his eight months in detention. They added he had lost 30 kilograms due to a hunger strike he had started to protest his detention. Elshamy was arrested on August 14 when police dispersed Rabaa Al-Adaweya, a massive Islamist protest camp in Cairo, killing hundreds in clashes. He has not been brought to court yet.