Chairwoman of the Karen Women’s Union Naw Ohn Hla has been detained under unlawful assembly charges for organizing a Karen Martyrs’ Day commemoration in Yangon last month without permission.

The long-term land rights and political activist, who herself is ethnic Karen, was arrested on Monday night and brought to the police station in Kyauktada Township, Ko Min Nay Htoo of the Democracy, Peace and Women’s Organization (DPW) said. Naw Ohn Hla also chairs the DPW.

Local authorities banned the use of the term “martyr” in reference to Karen revolutionary leader Saw Ba U Gyi, who was killed on Aug. 12, 1950. His death is commemorated annually as Karen Martyrs’ Day.

The 69th memorial was held—under the banner of Karen Martyrs’ Day—in front of city hall in Kyauktada Township this year. More than 100 people attended the event.

Police from Kyauktada Township opened cases against Naw Ohn Hla and two others under Article 20 of the Peaceful Assembly and Procession Law for organizing the unauthorized event.

Ko Min Nay Htoo said the two activists will also face lawsuits when they return, as they are currently out of town.

At a court appearance on Tuesday, Naw Ohn Hla declined to request bail.

“We didn’t do anything wrong. I am not seeking bail as this is unfair. We acted in accordance with the law [by informing authorities about the event in advance],” she told reporters outside the court.

Naw Ohn Hla was sent directly to Insein Prison after the court appearance.

The offenses carry one-month prison sentences, fines or both.