CNN reports hundreds of mourners marched to Seoul's Presidential Palace Saturday.
Most were North Korean defectors.
They mourned a mother who fled poverty in North Korea, only to die of suspected starvation in her small apartment in South Korea.
They marched with two symbolic empty caskets to South Korea's presidential office, eventually clashing with the police.
They demanded an apology from President Moon Jae-in, himself, for what they see as neglect of defectors' welfare.