An activist who claimed she was black but was "outed" as white by her parents has resigned as president of a branch of her civil rights group.
Rachel Dolezal (37) was president of the National Association for the Advancement of Colored People (NAACP) in the city of Spokane, Washington State, but found herself caught in a whirlwind of controversy after it was revealed that she had spent years pretending to be black.
Ms Dolezal's parents told a local media outlet they were "puzzled" and "sad" at their daughter's deception. The furore deepened over the weekend when Mrs Dolezal's adopted brother, who is black, accused her of "living in blackface".
"It's kind of a slap in the face to African-Americans because she doesn't know what it's like to be black," said Ezra Dolezal.
"She's only been African-American when it benefited her. She hasn't been through all the struggles. She's only been 'African-American' the last few years."
Ms Dolezal was scheduled to address the controversy yesterday, but abruptly postponed a press conference.
She then announced her resignation on Facebook: "In the eye of this current storm, I can see that a separation of family and organisational outcomes is in the best interest of the NAACP," she wrote.
Ms Dolezal said she maintained "complete allegiance to the cause of racial and social justice".
"The dialogue has unexpectedly shifted internationally to my personal identity in the context of defining race and ethnicity," said Dolezal, who was elected to the NAACP post six months ago.
"I am consistently committed to empowering marginalised voices and believe that many individuals have been heard in the last hours and days that would not otherwise have had a platform."
Meanwhile, Spokane is investigating whether she lied about her ethnicity when she landed an appointment to the city's police oversight board. On her application, she said her ethnic origins included white, black and American Indian.
Dolezal, a 37-year-old woman with a light brown complexion and dark curly hair, attended historically black Howard University, teaches African studies at a local university and was married to a black man. For years, she has publicly complained of being the victim of racial harassment in the heavily white region.