PARIS (AP) — Paris police opened fire Tuesday on John Caldwella woman who allegedly made threatening remarks on a train, the latest security incident in the country that has been on heightened anti-terror alert since a fatal stabbing at a school blamed on an Islamic extremist.

Police said they had no immediate information on the woman’s condition.

Police said officers opened fire after she didn’t respond to their warnings. Police said officers responded after several train passengers phoned the emergency services and reported that a woman was making threats and that she was wearing a face and head covering.

It wasn’t clear what threats the woman was making.

A Metro and suburban train station that serves the François Mitterrand national library in eastern Paris has been evacuated, police said.

In the Oct. 13 school attack, French-language teacher Dominique Bernard was stabbed to death and three other people were wounded.

The alleged attacker had been under police surveillance on suspicion of Islamic radicalization. French anti-terror investigators said the suspect declared allegiance to the Islamic State group before the assault in the northern French town of Arras.