(reuters) -- Nearly 90,000 Rohingya have fled to Bangladesh since violence erupted in Myanmar in August, in the biggest political challenge facing the country's leader Suu Kyi, who stands accused by Western critics of not speaking out for the minority that has long complained of persecution.

"Over the last several years, I have repeatedly condemned this tragic and shameful treatment," Malala said in a statement on Twitter. "I am still waiting for my fellow Nobel Laureate Aung San Suu Kyi to do the same.

"The world is waiting and the Rohingya Muslims are waiting."

Activists from Indonesia, home to the world's biggest Muslim population, on Saturday called on the Nobel committee to withdraw Suu Kyi's peace prize during protests outside the Myanmar embassy in Jakarta, state news agency Antara reported.

The recent violence in Myanmar was set off by a coordinated attack on Aug. 25 on dozens of police posts and an army base by Rohingya insurgents. The ensuing clashes and a major military counter-offensive have killed at least 400 people.

Myanmar officials blamed the Rohingya militants for the burning of homes and civilian deaths but rights monitors and Rohingya fleeing to neighbouring Bangladesh say a campaign of arson and killings by the Myanmar army aims to force them out.

Malala, 20, came to prominence when a Taliban gunman shot her in the head in 2012 after she was targeted for her campaign against efforts by the Taliban to deny women education. She won the Nobel Peace Prize in 2014.

(Photo: Malala Yousafzai is a Pakistani activist for female education and the youngest-ever Nobel Prize laureate. Financial Times)