A 31-year-old man has been charged with attempted murder in connection with a knife attack in Paris

Prosecutors said Sunday that a man was charged with attempted murder in France after seven people were injured with a metal hook at Paris’s Gare du Nord station last week.

According to prosecutor Laure Beccuau, investigators are still unsure of the motivation for the attack.

The identity of the 31-year-old suspect has not yet been formally established, she added.

While the investigation is ongoing, he is being held in custody.

The suspect was taken to the hospital after being shot and wounded during his arrest, but his condition had improved enough for him to be taken back into custody and placed under formal investigation.

The attack occurred on Wednesday at Paris’s Gare du Nord station, one of the busiest rail stations in Europe.

Investigators have not ruled out the possibility that the man had psychiatric issues.