Myanmar's military has expanded areas under martial law, which was already in place in some areas of the largest city, Yangon.

Martial law was imposed in 37 townships on Thursday. This came a day after the junta announced the state of emergency would be extended for six months.

Martial law gives the military more power over people's lives. Those charged with treason will be judged in a military court.

The measure is seen as a way to demonstrate the military's power, and step up the fight against pro-democracy opponents.

The areas now affected include Sagaing Region and Chin State in the country's northwest. Pro-democracy and armed ethnic groups have been continuing the fight there. Whether the junta can effectively exercise control is unclear.