PARIS (NY TIMES) - Four American women were attacked with acid by another woman Sunday at a train station in southern France, injuring at least two of them, according to local police.

The assailant, a 41-year-old woman, was quickly arrested in the Mediterranean port city of Marseille. The police prefecture said they were not treating the attack as a terrorist assault.

The suspect has "a psychiatric history", a spokesman for the police prefecture in Marseille said. "For now, nothing suggests that this was a terrorist attack."

The four Americans, all in their early 20s, were in front of the Saint-Charles train station when a woman threw hydrochloric acid on them shortly before 11 am.

Two of the women were burned, and the other two appeared to have escaped injury, but they were in a state of shock, according to police. All four were treated at a hospital Sunday.

The prosecutor's office could not be reached for comment but told France 3 that one of the women had been hit in the eye with acid and had trouble seeing. The women were not immediately identified.

France has been on high alert for terrorism since 2015, after a series of attacks killed more than 230 people. There have also been a number of attacks by psychologically unstable residents who have sometimes imitated terrorist acts, officials say.

La Provence, the main local newspaper, quoted police sources as saying that after the attack, the suspect had displayed pictures of herself with burns on her body. The prosecutor's office said the suspect also had a criminal record for violent theft, according to France 3.

In 2013, two American women, Kirstie Trup and Katie Gee, both 18, who were teaching on the island of Zanzibar, were attacked with acid by two men on a moped who stopped, smiled and doused them, severely burning their faces, chests and hands, before speeding away.