Story highlights Police investigating not only rape allegations but also possible violations of Brazil's Internet laws

A 38-second video of the girl, naked and unconscious, has circulated on social media

Rio de Janeiro (CNN) Brazilian police are searching for at least 30 people suspected in the alleged gang rape of a 16-year-old girl and of posting graphic video and images of her on social media that have shocked the South American country.

The perpetrators put up pictures and a video of the girl on Twitter, sparking a nationwide backlash. The incident occurred in a Rio de Janeiro slum over the weekend.

At a press conference Friday, police said they had identified four people who were involved, including one man who appeared in the video, the girl's boyfriend and two people who were heard on the video.

Police are investigating not only rape allegations but also possible violations of Brazil's Internet laws

The state-run Agencia Brasil news agency said Saturday a man who taken into custody for questioning. Seventy officers were involved in the search for suspects and drugs were seized, Agencia Brasil said.

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