Story highlights Sexually explicit videos of Tiziana Cantone went viral online

Cantone, 31, committed suicide this week, reports say

(CNN) The family of Tiziana Cantone, an Italian woman who committed suicide after sexually explicit videos of her went viral on the Internet, has urged the Italian authorities "to act so that her death was not in vain."

The 31-year-old was found hanged Tuesday at her aunt's home in Mugnano, near Naples, in the south of the country, according to media reports.

Four people are under investigation by criminal prosecutors over alleged defamation of the woman, Italian state media ANSA reported.

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Cantone sent the video to friends, who published it online without her knowledge, ANSA said. More than a million people watched it, and she became the target of abuse.

The phrase "You're filming? Bravo," which she says to her lover in the clip, went viral online and was printed on T-shirts, smartphone cases and other paraphernalia.