CAIRO, May 30 (Reuters) - Egyptian prosecutors on Monday ordered the head of the journalists union and two board members to be tried on charges of harbouring colleagues wanted by the law, judicial sources said, a move that drew condemnation from rights groups.

The trial of Yehia Qalash, Khaled al-Balshy, and Gamal Abdel Rahim will begin on Saturday at a Cairo misdemeanours court, the judicial sources said.

The charges of harbouring fugitives and spreading false news about a police raid of the union premises carry a maximum sentence of three years in jail, according to a legal expert. The prosecutors have not said what sentence they will seek.

The journalists' lawyer Sayyed Abou Zeid told Reuters they denied the charges, which relate to a May 2 police raid on the Egyptian Journalists Syndicate to arrest two opposition journalists who had sought shelter from arrest inside.

Qalash and the union condemned the arrests of Mahmoud El Sakka and Amr Badr, which sparked protests from journalists, and issued a statement two days later demanding the interior minister be sacked.

Union officials said at the time that police had stormed the building for the first time in its 75-year history. The interior ministry denied that but confirmed police had arrested Sakka and Badr, who work for the opposition website Bawabet Yanayer and were wanted on criminal charges.

Monday's decision to charge the journalists come as authorities try to quell rising dissent against President Abdel Fattah al-Sisi.

Thousands of demonstrators called on April 15 for "the fall of the regime", a slogan from the 2011 uprisings that ended Hosni Mubarak's 30-year rule. Police dispersed smaller protests two weeks later and arrested scores of people.

Amnesty International urged the authorities to drop the charges.

Qalash and his colleagues initially went to a Cairo police station for questioning on Sunday and were unexpectedly charged and ordered to pay bail of 10,000 Egyptian pounds ($1,126.15) each, Abou Zeid and another union board member said.

They initially refused to pay but were later freed after security sources said another party paid the bail. ($1 = 8.8798 Egyptian pounds)

(Reporting by Mohamed Abdellah, Haitham Ahmed and Lin Noueihed; editing by Andrew Roche and Diane Craft) ((lin.noueihed@thomsonreuters.com; +202 2 394 8039; Reuters Messaging: lin.noueihed.thomsonreuters.com@reuters.net))