Céline Vervaele, 29, has not given any sign of life for three weeks to the day.
Information was opened on Thursday for "kidnapping" and "kidnapping", the Rennes prosecutor's office told BFMTV.
An evolution which should make it possible to
"continue the investigations and research in a more suitable framework"
, according to Philippe Astruc, the public prosecutor of Rennes.
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The young woman from the Vosges left the marital home in the Cleunay district in Rennes on March 13 at the end of the afternoon after an argument with her companion, a 51-year-old man.
It was the latter who raised the alarm.
She wouldn't have taken her phone or papers with her.
Two days after his disappearance, the Rennes police called for witnesses while an investigation for "disturbing disappearance" was opened.
From this call for witnesses emerged the testimony of a person affirming that Céline Vervaele would have been taken hitchhiking on March 16.
Read also: Ille-et-Vilaine: call for witnesses after the worrying disappearance of a 29-year-old Vosges woman living in Rennes
"
This testimony has not for the moment been able to be corroborated by other elements accrediting with more certainty a voluntary disappearance
", underlined the prosecutor of Rennes Philippe Astruc to
BFMTV
.
And the magistrate to add that the couple, together for 8 years
"was in reflection on a possible separation"
.
The day before her disappearance, Céline Vervaele also left a letter to her spouse in which she evokes a sentimental relationship with another man.
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This week the divers from the gendarmerie dredged the waters of the Vilaine in search of the missing young woman, to no avail.
"All the leads concerning the disappearance of Céline Vervaele are studied"
, indicated the national police of Ille et Vilaine on Twitter.
An emergency number
Céline Vervaele has freckles, shoulder-length red blonde hair and blue eyes.
She wears prescription glasses and is five feet tall. When she left home she was wearing gray pants with a green and yellow checkered shirt and jacket.
If you have any information, please contact the police station in Rennes: 02 99 79 86 09 or 02 99 79 86 98.