Alphabet Inc.’s Google has removed hundreds of negative reviews for a tracker that identifies apparel brands linked to forced Uyghur labor after its creator said the reviews were part of a disinformation campaign.

The Human Rights Foundation’s Uyghur Forced Labor Checker had been experiencing a spate of unusual activity in recent months, with the number of downloads fluctuating dramatically, according to Claudia Bennett, the nonprofit’s legal and program officer. The tool, a Google Chrome extension, alerts internet users if a retailer or business whose website they are visiting has links to forced Uyghur labor.

Human Rights Foundation won a Webby People’s Voice award in public service and activism in 2022. In May, the organization’s legal department alerted Google to a barrage of one-star ratings, which they suspected were part of a computer bot attack. The reviews in question came from accounts using similar cartoon avatars as profile pictures, had nonsensical first and last names, and spoke in broken English, according to screenshots seen by Bloomberg News.

“Malicious slander,” one of the reviews stated. “Leakage of privacy,” claimed another. A third said, “Isn’t it too boring.”

A Google spokesperson said the company carefully monitors the Chrome Web Store and removes reviews that violate its policies, including those removed from the Uyghur Forced Labor Checker. It wasn’t clear who was behind the negative reviews.

The US has accused China of forcing Uyghurs in the Xinjiang region to work under what officials have described as a broader campaign of genocide.