The military coup has taken place as Myanmar’s army claims the country’s elections – held in November last year – were fraudulent. In November’s election, Ms Suu Kyi’s National League for Democracy (NLD) won enough seats to form a government.
Ms Suu Kyi was arrested along with other leaders just hours ago.
The US has blasted the move, warning it will “take action against those responsible if these steps are not reversed”, according to White House spokesperson Jen Psaki.
The new military rule is not the first time the country has come under control of its own army.
Myanmar, also known as Burma, was military-ruled until democratic reforms began in 2011, the BBC reports.
In a television broadcast, the military confirmed it was taking control of the country for the next year.
The coup comes just hours before Ms Suu Kyi’s NLD party was due to convene in parliament for the first time. The military had called for the event to be delayed.
Power is now understood to be in the hands of commander-in-chief Min Aung Hlaing, and soldiers are on the streets.
The coup follows days of tensions between Myanmar’s former government and the military.
Aung San Suu Kyi is the daughter of General Aung San – who was seen as a figure of Myanmar independence, analysts say.
He was assassinated shortly before Myanmar gained independence from Britain in 1948.
Ms Suu Kyi has challenged Myanmar’s army generals before. However, she has also faced criticism over the country’s widespread mistreatment of its Muslim Rohingya community, who suffered a deadly military crackdown in 2017 later referred to by the United Nations as a “textbook example of ethnic cleansing”.
She is not technically the country’s president, but she is widely viewed as the country’s ‘de facto’ leader, according to the BBC.