French authorities have opened an investigation after a teenager allegedly live-streamed video of her suicide on the popular app Periscope.

The local prosecutor said Wednesday the young woman threw herself under a commuter train in the suburban Egly station, south of Paris, after claiming she had been raped by her former boyfriend. The prosecutor's statement said the woman was born in 1997, so she was 18 or 19.

The teenager, whose name was not released, sent a text message to a friend of her former boyfriend a few hours before she killed herself Tuesday, prosecutor Eric Lallement said.

"In the text message, she mentions violence and a rape that her companion inflicted on her and claims she is ending her days because of the harm that the young man had done to her," Lallement said.

On Tuesday, the woman spent more than two hours overall on Periscope, divided in five live sessions. The last one lasted 29 minutes and seemed to have been recorded moments before she killed herself, he said.

The teen's video messages and cellphone have been seized by the police. An autopsy and toxicology and drug tests will be conducted over the next few days.

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In her own messages, the woman spoke a lot about her life and her difficult relationship with her former boyfriend, Lallement said.

The video has been removed from Periscope, a cellphone live video-streaming app particularly popular among young people, but YouTube users posted what they said were excerpts. The suicide scene itself is not visible on YouTube.

Periscope, owned by Twitter, did not publicly comment.

The French case is only the latest one linked to Periscope. Last month in Ohio, a 17-year-old woman was raped by a man with whom she had been drinking and her 18-year-old friend live-streamed the attack on the social media app, prompting a prosecutor to file a rape and kidnapping indictment.