A labor rights group published an investigation Thursday detailing sexual harassment and violence against women working at three textile factories in Africa sewing brand-name blue jeans. Among the findings were that some female workers were coerced into having sex with their supervisors to keep their jobs.

The report by the Worker Rights Consortium (WRC), a labor rights group, claims that women sewing blue jeans for Levi's, Wrangler, Lee and The Children's Place faced sexual harassment and violence. The WRC said it spent two years investigating labor practices and interviewing women in Maseru, Lesotho — a poor, mountainous kingdom encircled by South Africa — and found the abuses had occurred across three factories.

"The gender-based violence and harassment identified at these facilities violated workers' rights under Lesotho's labor laws, international standards, and the codes of conduct of the brands whose products those employees produce," the report states.

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In response to the group's findings, the brands have agreed to bring in outside oversight and enforcement for more than 10,000 workers at five Lesotho factories, the report states.

WRC began investigating Taiwan-based Nien Hsing Textile factories, the owner of the three factories in Lesotho, after hearing from a number of sources that women who produced the blue jeans and other clothes by hand faced gender-based violence.

Managers and supervisors forced many female workers into sexual relationships in exchange for job security or promotions, the report says. In dozens of interviews, the women described a pattern of abuse and harassment, including inappropriate touching, sexual demands and crude comments.

The report said that when the workers objected to the treatment, they faced retaliation, and the factory managers also fought union organizing.

"The vulnerability of women workers at these factories to gender-based violence and harassment was exacerbated by Nien Hsing's suppression of workers' associational rights, which left employees unable to act collectively to raise concerns about, and demand an end to, these abuses," the report said.

While most of the employees are from Lesotho, managers were both locals and foreign. The workers' testimony in the report is anonymous to protect their privacy.

"Male workers like touching females in a way that is not appropriate," one worker said.

"The foreign national managers slap women's buttocks and touch their breasts. They sometimes take them home for sex," another worker said.

Levi Strauss & Co. vice president of sustainability Michael Kobori said that as soon as the company received the Worker Rights Consortium report it told Nien Hsing "that this would not be tolerated and required them to develop a corrective action plan." A spokesperson for The Children's Place said it informed the firm that their ongoing relationship "depends on effectuating significant and sustained changes."

Levi's, The Children's Place and Kontoor Brands, maker of Wrangler and Lee jeans, said in a joint statement they want all workers, especially women, to feel "safe, valued and empowered."

The U.S. companies are funding a two-year program, in collaboration with the U.S. Agency for International Development, that establishes an independent investigative group where factory workers can raise concerns.

Factory owner Nien Hsing has agreed to work with Lesotho-based unions and women's rights organizations to develop a code of conduct and enforcement actions.

"We strive to ensure a safe and secure workplace for all workers in our factories," Nien Hsing Chairman Richard Chen said in a written statement. Besides its mills and manufacturing facilities in Lesotho, the company also has facilities in Mexico, Taiwan and Vietnam.

About 80 percent of garment makers around the world are women, according to the Global Fund for Women.