A lawyer for a detained opposition leader in Uganda says he is concerned for the safety of his client, who was charged with treason last week because of his anti-government protests.

Ladislaus Rwakafuuzi said Monday that opposition leader Kizza Besigye, who has been in detention since Wednesday, is being held in an unsanitary jail many miles from the capital and without access to his legal team. Rwakafuuzi said there are also concerns Besigye could be the victim of a plot to poison him, although he gave no specific details.

Besigye, who came second in a presidential election held in February, is being detained in a remote area in northeast Uganda. He was flown there after being arrested on Wednesday in the capital Kampala.

Besigye claims he won the election.