YANGON (Reuters) - Three Myanmar journalists accused of breaking the law by covering an event hosted by a rebel army were defiant as their trial began in the country’s northeast on Friday, in a case that has raised concerns about freedom of expression.

Reporters protest as they call on Myanmar government and military authorities to release reporters who were arrested in Yangon, Myanmar June 30, 2017. REUTERS/Soe Zeya Tun NO RESALES. NO ARCHIVES

Reporters Aye Nai, Pyae Phone Aung and Lawi Weng are charged under the Unlawful Associations Act - a colonial-era law that includes broadly worded prohibitions on contacts with banned groups. They face up to three years in prison each if convicted.

“We have no regret. We are doing the right thing. So we have no fear,” Aye Nai said outside the court in Hsipaw, Shan state, footage from Democratic Voice of Burma (DVB) showed.

“We have got this because we are journalists,” said Lawi Weng, pointing to his handcuffs. “This is our country’s democracy.”

The reporters are from two media outlets publishing both in Burmese and English, the DVB and the Irrawaddy. They were among the few media organizations providing the world independent coverage of Myanmar when it was under military rule before a democratic transition began in 2011.

Nobel laureate Aung San Suu Kyi - who serves as Myanmar’s foreign minister and is de facto head of its civilian government - has said the reporters’ case was a matter for the courts.

She remains constrained by a constitution that protects the military’s role in the country’s politics.

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The case has raised concerns that the military is muzzling reporting on its conflicts with myriad armed groups that claim to fight on behalf of ethnic minorities seeking more autonomy.

“This is a clear attempt by the authorities to intimidate journalists and silence their critical coverage,” James Gomez, Amnesty International director for Southeast Asia and the Pacific, said in a statement ahead of Friday’s hearing.

“It is exactly in northern Shan State and the other ethnic areas wracked by conflict, where appalling human rights abuses are rife, that independent journalism is needed the most.”

The journalists and three other men were detained by soldiers on June 26 while returning from an event where the Ta’ang National Liberation Army set alight narcotics to mark the international day against drug abuse and illicit trafficking.

The military held the men for two days before handing them to police and filing a legal complaint.

On Friday, a military officer gave evidence and the defendants applied for bail before court was adjourned until Aug. 4, said Maung Maung Win, DVB’s lawyer.

“We will defend them by the law. Journalists have a right to cover the news from both sides in the conflict,” he said, referring to the country’s media law.

The journalists argued in the video that they were simply doing their jobs, and should be vindicated by the court.

“Teachers will teach. Doctors will cure. We journalists will do our work,” said Pyae Phone Aung. “Thus we don’t have to plead for pardon.”

Military spokesmen have declined to comment on the case.