A spokesman for the ruling National League for Democracy (Nasr) confirmed that the former president was being held by the military, along with other senior members of its executive council.
Meanwhile, the country is embroiled in tensions between the civilian government and military leaders who have accused the country of mismanagement.
Even in last November's election, the president's party won enough seats to form a government, but the military is adamant that the election was rigged.
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What is the current situation?
A military statement said power had been handed over to the country's top military commander, Min Aung Hlaing, without delay.
The country's radio and television stations have been shut down, and telephone and internet lines have been cut off.
Soldiers can be seen patrolling the streets, on the streets of the capital Naypyitaw and the capital Yangon.
Our recent information confirms that the coup forces imposed a state of emergency in parts of the country.
The country's parliament should have reconvened to extend the term of the ousted president, but for now it will be up to the military to decide.
