Burma's detained opposition leader Aung San Suu Kyi has reportedly been taken from her home in Rangoon to the notorious Insein prison.
A court will be convened at the jail to hear charges against her relating to a secret visitor to her home.
A spokesman for Ms Suu Kyi's National League for Democracy party says the pro-democracy leader will be charged over an incident last week where an American man swam across a lake and reportedly spent two days in her home.
The authorities caught him when he was swimming back.
Security measures have been been beefed up around her home as a result.
Ms Suu Kyi has been under house detention for 13 of the past 19 years since she won national elections in 1990.
Her latest home detention order is due to lapse in less than two weeks.
She has been suffering poor health in recent days.