A Vietnamese court was scheduled to hear an appeal Thursday from pastor Duong Kim Khai and several other land rights activists who were convicted of subversion at a closed one-day trial in May.

An eight-year sentence was handed on May 30 to activist Tran Thi Thuy, who was identified as a member of the banned opposition group Viet Tan. Sentences ranged between two and seven years for the others, including Khai and two other members of an unsanctioned Mennonite group known as the Cattle Shed Congregation.

U.S. officials complained at the time that some of the defendants were denied access to lawyers before the trial in southern Ben Tre province.

U.S.-based Viet Tan, or Vietnam Reform Party, acknowledged on its website that three of the seven were members of the party. It said Khai and the others had been offering legal advice to farmers whose land has been seized by the government to make way for developments.

A Vietnamese news report said some of the defendants had traveled to Thailand and Cambodia for training on how to overthrow the government by non-violent means.

Viet Tan said some of the defendants had exercised their right to attend courses on non-violent struggle.