Their lawyers have said the charges against both of them were trumped up.
At least 538 civilians have been killed in protests against the coup, 141 of them on Saturday, the bloodiest day of the unrest, according to the Assistance Association for Political Prisoners (AAPP) activist group.
Protesters were back out in several places on Thursday and two more people were killed, according to media reports, as activists burned copies of a military-framed constitution and called for unity among all those opposed to army rule.
Turnell revealed in early February he was being detained, the first-known arrest of a foreign national since the coup that overthrew Suu Kyi's elected government.
The military seized power saying that the November elections won by Suu Kyi's party were fraudulent. The election commission said the vote was fair.
Myanmar has been in turmoil since the reimposed military rule after a decade of tentative steps toward democracy.
The United Nations special envoy on Myanmar, Christine Schraner Burgener, this week told a session of the UN Security Council that "a bloodbath is imminent" because of the military's intensified crackdown on anti-coup protesters.
Schraner Burgener told a closed session of the 15-member council the military that seized power in Myanmar on February 1 was not capable of managing the country and warned the situation on the ground would only worsen.
"Consider all available tools to take collective action and do what is right, what the people of Myanmar deserve, and prevent a multi-dimensional catastrophe in the heart of Asia," she said.
The council must consider "potentially significant action" to reverse the course of events as "a bloodbath is imminent", Schraner Burgener said.
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