Myanmar’s military has taken control of the country after detaining de facto leader Aung San Suu Kyi and other politicians in the early hours.
Military TV said a state of emergency had been declared for one year and power transferred.
The coup comes after tensions rose between the civilian government and the military following a disputed election.
In November’s election, Ms Suu Kyi’s National League for Democracy (NLD) won enough seats to form a government.
The NLD won 83% of available seats in the 8 November election in what many saw as a referendum on Ms Suu Kyi’s civilian government.
It was just the second election since the end of military rule in 2011.
But the military has disputed the result, filing complaints at the Supreme Court against the president and the chair of the electoral commission.
Fears of a coup rose after the military recently threatened to “take action” over alleged fraud. The election commission has rejected the allegations.
The military said on Monday it was handing power to commander-in-chief Min Aung Hlaing because of “election fraud”. Soldiers are on the streets of the capital, Nay Pyi Taw, and the main city, Yangon.
Mobile internet data connections and some phone services have been disrupted in major cities, while the state broadcaster MRTV says it is having technical issues and is off air.
Communications with Nay Pyi Taw are down and it is difficult to assess the situation there.
In the country’s largest city and former capital Yangon, phone lines and internet connectivity appear to be limited, with many providers cutting their services.
International broadcasters are blocked, while local stations are off air.
The United States has condemned the coup, saying Washington “opposes any attempt to alter the outcome of recent elections or impede Myanmar’s democratic transition”.
US Secretary of State, Antony Blinken, called for the release of all government officials and civil society leaders and said the US “stands with the people of Burma in their aspirations for democracy, freedom, peace, and development. The military must reverse these actions immediately”.
Myanmar, also known as Burma, was ruled by the military until democratic reforms began in 2011.
Aung San Suu Kyi is the daughter of Myanmar’s independence hero, General Aung San who was assassinated just before Myanmar gained independence from British colonial rule in 1948.
She spent nearly 15 years in detention between 1989 and 2010.
Ms Suu Kyi was once seen as a beacon for human rights – in 1991, she was awarded the Nobel Peace Prize, while still under house arrest, and hailed as “an outstanding example of the power of the powerless”.
In November 2015 she led the National League for Democracy (NLD) to a landslide victory in Myanmar’s first openly contested election for 25 years.
The constitution forbids her from becoming president because she has children who are foreign nationals but the 75-year old, is widely seen as de facto leader.
In recent years, her leadership has been defined by the treatment of the country’s mostly Muslim Rohingya minority.
Ms Suu Kyi’s former international supporters accused her of doing nothing to stop rape, murder and possible genocide by refusing to condemn the military or acknowledge accounts of atrocities.
At home, however, “the Lady”, as Ms Suu Kyi is known, remains wildly popular among the Buddhist majority who hold little sympathy for the Rohingya.