The United States says it is "deeply troubled" by the death in Burma of jailed pro-democracy activist Thet Win Aung.
In a statement Wednesday, the U.S. State Department said the death shows the "tragic price" the people of Burma are forced to pay for opposing Burma's repressive policies and seeking human and democratic rights.
Thet Win Aung was arrested in 1998 for organizing student protests and sentenced to 59 years in prison.
Family members said prison officials notified them Monday about the death. Human rights groups are demanding an investigation.
The United States also condemned the continued detention of six pro-democracy activists in Burma who were arrested in September - Min Ko Naing, Ko Ko Gyi, Htay Kywe, Min Zeya, Pyone Cho, and Myint Aye.
The statement called for the immediate and unconditional release of the six, as well as that of all political prisoners in Burma.
Information for this report is provided by AFP.