MEXICO CITY (AP) — The U.N. human rights agency called on Mexican authorities Thursday to thoroughly investigate the killing of an LGBT rights activist in the northern Mexico state of Chihuahua.

The office of the U.N. High Commissioner for Human Rights said Mireya Rodríguez Lemus was found dead in her home in the Chihuahua town of Aquilles Serdan on Sept. 2 but official identification of the body was not made until Tuesday.

The agency said she had been found with signs of a violent death. It said she was at least the seventh rights activist killed in Mexico so far in 2020.

Rodríguez Lemus was a founder of a transgender advocacy group and a promoter of AIDS education and prevention campaigns.

Her group, the Union and Force of Chihuahua Trans Women, said she had gone missing from the areas she used to frequent as a sex worker and activist several days before her death.