Yemen’s Houthi rebels must stop the planned trial of 10 journalists and release all detained media professionals detained as part of a campaign of intimidation of the press, the Committee to Protect Journalists (CPJ) said on Sunday.

Ten Yemeni journalists have been in rebel detention since 2015 and were formally charged by the rebels in December 2018 on claims of spying and aiding the Arab-led coalition that has been attempting to restore the government of President Abdrabu Mansur Hadi.

The journalists, all men, could face the death penalty if found guilty in the Houthi controlled courts that investigated and brought charges against them, the CPJ said. The body said that journalists have reported that Houthi authorities consider them indistinguishable from armed combatants – in contravention to the Geneva Convention.

"The Houthis have demonstrated their brutality by holding at least 10 journalists in what by all accounts are deplorable conditions for nearly four years," CPJ Middle East and North Africa Program Coordinator Sherif Mansour said in a statement.

"Journalists are not combatants and they must not pay the price for Yemen's conflict. The Houthis should immediately release all journalists in their custody,” Mr Sherif said.

Houthi guards have allegedly tortured and mistreated the reporters in their prisons in Sanaa, according to families of the detainees.

One of the detainees, graphic designer Tawfiq Al Mansouri, was beaten by the guards "with sticks, cables, iron bars, rifle butts, and their fists, as well as by being forced to hold cinder blocks for several hours and preventing him from drinking water for up to a day," Mr Al Masouri's brother, Abdulla Al Mansouri, told CPJ.

Mr Al Mansouri has not been allowed to visit his brother during Ramadan but says he is in poor health.

The committee has documented the detention and abuse of all the journalists but said it could not independently verify the allegations of torture and mistreatment.

Yemen has been plunged into a civil war since 2014 after the Iranian-backed group seized its capital, Sanaa, and ousted the internationally recognised government from power.

The government has been consistent in calling on the international community to exert pressure on the rebels to go through with a prisoner exchange deal agreed during UN peace talks in Sweden last December.

“We hope before Eid thousands of Yemeni politicians, journalists and activists taken by the Houthis would be returned home with their families,” Yemen’s Minister of Information, Muamaar Al Eryani said on Twitter.

It is not clear if the men are included in the government’s list of people they want freed by the Houthis.

Officials in government have vowed to continue to pressure the rebels to release all detainees.

Amnesty International, last month, called on the Houthis to free the men held for nearly four years on what the rights group described as "trumped-up" spying charges.

As well as Mr Al Mansouri, the other journalists are Abdulkhaleq Amran, Hesham Tarmoum, Hareth Hameed, Akram Al Waleedi, Essam Balghaith, Hisham Al Yousifi, Haitham Al Shihab, Hassan Anaab and Salah Al Qaedy.AFP.