A U.S.-based human rights group says Burmese authorities have arrested a lawyer who is defending members of Burma's opposition party.

The U.S. Campaign for Burma says police detained Nyi Nyi Htwe in Rangoon Wednesday and are holding him in the Hlaing Thar Yar police station.

The group says Nyi Nyi Htwe and another lawyer Saw Kyaw Kyaw Min are defending 11 youth members of the National League for Democracy who were arrested in September for inciting public unrest.

Authorities detained the activists for peacefully marching to Rangoon's Shwedagon Pagoda on June 19, 2007 - the birthday of detained opposition leader Aung San Suu Kyi.

The U.S. Campaign for Burma says the activists were not given a fair trial. It says when the lawyers submitted complaints about the process, the judge allowed the prosecutor to sue the lawyers and three defendants.

Burma is ruled by a military government that suppresses any opposition to its rule.

Last year, a string of small, peaceful protests against the rising cost of fuel turned into a rare massive anti-government movement calling for democratic reforms.

The military crushed the demonstrations with force.