Human rights lawyer Amal Clooney will represent two journalists detained in Burma.
Wa Lone and Kyaw Soe Oo - reporters for the Reuters news agency - are being held in a Yangon prison after being arrested in December.
They are being held under the country's Official Secrets Act, a statute which carries a maximum prison sentence of 14 years.
The journalists had been working on an investigation into the massacre of 10 Rohingya men and boys in the Rakhine State.
Barrister Ms Clooney, who specialises in international law and human rights, confirmed on Thursday that she has joined their legal team.
"Wa Lone and Kyaw Soe Oo are being prosecuted simply because they reported the news," she said.
"I have reviewed the case file and it is clear beyond doubt that the two journalists are innocent and should be released immediately.
"Yet they have been denied bail and face 14 years in prison.
"The outcome of this case will tell us a lot about Myanmar's commitment to the rule of law and freedom of speech."
Gail Gove, Reuters' chief counsel, added: "We will pursue all avenues to secure our reporters' release.
"Retaining Ms Clooney greatly strengthens our international legal expertise and allows us to broaden those efforts."