An American journalist detained in Myanmar since last month appeared Thursday for the first time in a special court facing charges of working to foment dissent against the country's military government.

Danny Fenster, who is the managing editor of the website Frontier Myanmar, appeared in a special court in Yangon's Insein Prison where he is being held for allegedly violating section 505-A of the country's penal code, Frontier Myanmar said in a statement.

If he is found guilty, he could face up to three years in prison.

Fenster is scheduled to have another hearing on July 1.

"No reason was given for the filing of the charge against him," Frontier Myanmar said. "We know that Danny has done nothing to warrant this 505-A charge."

Fenster was arrested May 24 at Yangon's airport as he tried to leave the country.

"We condemn his detention and demand his immediate and unconditional release," Frontier Myanmar said.

Bryan Fenster, Danny's brother, tweeted that there was "finally some movement" on his brother's case, but said "frustration is mounting" as the hearing took place "without official communication with the U.S. Embassy or our family."

He lamented his brother's "continued detainment without access to legal counsel or official charges against him."

Another American journalist, Nathan Maung, who was detained in March for allegedly violating 505-A, was released Monday and left the country.

Two Myanmar journalists were jailed for two years under the law, The Associated Press reported earlier this month.

The military took power February 1, overthrowing the civilian government and detaining de facto leader Aung San Suu Kyi and other high-ranking officials.

Since the coup, widespread protests have rocked Myanmar, many of them turning violent as government officials cracked down. Hundreds of civilians, including dozens of children, have been killed by government troops and police since the coup.

The U.S has sanctioned military leaders, some of their family members and other businesses in the country.

The U.S. has also called for the immediate release of Aung San Suu Kyi, leader of the National League for Democracy Party, ousted President Win Myint, and protesters, journalists and human rights activists it says have been unjustly detained since the coup.

Military officials claimed widespread fraud in last November's general election, which Aung San Suu Kyi's National League for Democracy won in a landslide, as justification for the February takeover. The fraud allegations have been denied by Myanmar's electoral commission.