She was held in detention overnight and released on bail by Sunday afternoon.

On Sunday, local television news stations broadcast protesters stomping on a Chinese flag and spraying it with black paint before dumping it in a river during a pro-democracy rally at a shopping mall in the Sha Tin neighborhood in northern Hong Kong.

A local ordinance says that people convicted of desecrating the Chinese flag in Hong Kong by “publicly and willfully burning, mutilating, scrawling on, defiling or trampling on it” face a fine of nearly $6,400 and imprisonment for up to three years.

Under Hong Kong law, children are defined as being under 14 years of age. Those 10 or older can be found guilty of committing crimes, but no one younger than 14 can be sentenced to prison.

The Oct. 1 holiday will commemorate the 70th anniversary of the founding of the People’s Republic of China under the Communist Party. Beijing does not want anything to mar the occasion, but the protesters plan to do just that. They have called for a day of protests to pressure the local government to meet their demands for political reforms, police accountability and universal suffrage.