A group of Native Americans pressed Sen. Elizabeth Warren to make a more convincing statement disavowing her past claims of having Native American heritage.

“Whatever your intentions, your actions have normalized white people claiming to be Native, and perpetuated a dangerous misunderstanding of tribal sovereignty,” the group of 200 Cherokees and other Native Americans told the Massachusetts Democrat in a letter reported by the Los Angeles Times on Wednesday. “Your actions do not exist in a vacuum but are part of a long and violent history.”