BERLIN (AP) — A prominent German environmental group said Wednesday that it's suing Facebook's parent company Meta over persistent death threats posted on the social network against its staff.

Environmental Action Germany, known by its German acronym DUH, says Meta has been unwilling to stop the threats of violence regularly directed at DUH director Juergen Resch and others in a Facebook group with more than 50,000 members.

DUH has conducted high-profile campaigns demanding that German cities enforce air quality rules by banning certain heavily polluting vehicles.

Meta didn't immediately respond to a request for comment.

German lawmaker Renate Kuenast won a case against Facebook last year forcing the company to remove fake quotes attributed to her from its site and pay damages. Facebook is appealing the ruling.