A 12-year-old girl is set to face charges after threatening a teacher with a knife in an apparent murder attempt at a French school on Wednesday.

Although no one was hurt during the incident in the northern city of Rennes, prosecutors announced they have initiated a criminal inquiry into attempted murder, the latest incident in the country's increasingly strained educational system.

PHOTO | COURTESY Schoolgirl Attempts To Kill Teacher With Knife In School

The child, who was born in 2011, "came to class armed with a large knife with the apparent intention of killing her English teacher," according to Rennes prosecutor Philippe Astruc.

"During the lesson, in class, she brandished the knife at the victim who fled running," before the girl was disarmed by staff of the Hautes Ourmes junior high school, he added.

"The pupils, shocked, were immediately moved to safety," the local education authority said.

At a news conference, Astruc demonstrated designs of a kitchen knife that he said was 17 centimetres (6.7 inches) long.

Astruc said in a statement Wednesday that the girl underwent mental evaluations in the hospital, which decided that "the minor was 'dangerous for herself' and that her condition required care in a specialised environment."

PHOTO | COURTESY prosecuter

The prosecution earlier stated that the "psychological or even psychiatric aspect" appeared "dominant in the act" by the girl.

The suspect is the eldest of four children in a Mongolian family with French residency who moved to Rennes in 2012.

Tensions have been developing in France's schools, which have strong Muslim and Jewish communities and have been related to the conflict between Israel and the Palestinian Islamist group Hamas.

In the northern town of Arras in October, a radicalized Islamist stabbed his former teacher to death.