Passengers look at information monitors at the Saint-Charles Station in Marseille, France, in August. (Bertrand Langlois/Agence France-Presse/Getty Images)

Four American college students were hospitalized Sunday after a woman sprayed them with acid at a train station in Marseille, a city in southern France, authorities say.

The victims, who are juniors at Boston College, were treated for burns and have been released, according to a statement from the college. Two had facial injuries, one of whom possibly suffered an eye injury, a spokeswoman for the Marseille prosecutor’s office told the Associated Press.

Investigators are not considering the attack a terrorist act, although that could not be ruled out early in the investigation. The spokeswoman told the AP that the suspect did not make extremist threats.

The attack happened about 11 a.m. at the Marseille-Saint Charles train station. Fourteen firefighters in four rescue vehicles responded, according to media reports.

Boston College said the young women are enrolled in the school's international programs. Three, Courtney Siverling, Charlotte Kaufman and Michelle Krug, are attending school in Paris; Kelsey Kosten is a student at the Copenhagen Business School in Denmark.

“It appears that the students are fine, considering the circumstances, though they may require additional treatment for burns,” Nick Gozik, director of Boston College's office of international programs, said in the statement. “We have been in contact with the students and their parents and remain in touch with French officials and the U.S. Embassy regarding the incident.”

La Provence, a newspaper in Marseille, reported that police described the attacker as mentally unstable and that she remained at the scene to show officers pictures of herself with burns. Authorities did not release her name.

Alex Daniels, a spokesman for the U.S. Embassy in Paris, told the AP that the embassy is not commenting on the incident, citing privacy reasons. He said the U.S. consulate in Marseille is in contact with investigators.

The port city of Marseille, about 500 miles southeast of Paris, has been the site of at least two other attacks in recent months.

In August, a man driving a van crashed into two bus stops in the Vieux-Port area, a popular tourist spot. One person was killed and another was injured, French media reported. Officials did not think it was a terrorist act.

In January, authorities said a 15-year-old Turkish Kurd attacked a Jewish teacher with a machete and claimed he did so on behalf of the Islamic State. The teenager struck the teacher’s shoulder and fled before police came.

One attack, which was supposed to happen in April leading up to the French presidential election, was thwarted. Authorities said two French nationals were arrested in Marseille before they were able to carry out what Paris prosecutor Francois Molins called an “imminent, violent action.”

In Britain, authorities said acid attacks have tripled in the past three years, stoking fears that anyone in a public area could be a victim. The alarming rise comes amid a clampdown on weapons and fears of a frightening new crime fad involving teenage motorbike thieves using corrosive substances, in part because they are relatively easy to obtain, The Washington Post reported last month.

Andreas Christopheros, an acid attack victim, is calling on the British government to enforce longer prison sentences for people who use corrosive substances to commit crimes. (Reuters)

Nearly 460 acid attacks were reported in London in 2016, according to London police. Deputy Metropolitan Police Commissioner Craig Mackey said investigators think the spike reflects an emerging trend among criminal gangs.

“We are seeing some links — although it has to be treated with caution because it’s a small data set — of a growing feature between named suspects in acid attacks who also feature in our gang matrix,” Mackey said.

Karla Adam, William Booth and James McAuley contributed to this report.

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