Image via AP.

Four Boston College students were attacked with acid at a train station in Marseilles, France on Sunday, leaving at least two of them injured.

According to CNN, all four victims were women in their early 20s who were studying abroad. Three of the students—identified as Courtney Siverling, Charlotte Kaufman and Michelle Krug—are juniors based in Paris, while the fourth, Kelsey Kosten, is a junior studying at Copenhagen Business School in Denmark. They were treated for burns at a hospital and have since been released.

“It appears that the students are fine, considering the circumstances, though they may require additional treatment for burns,” Nick Gozik, who directs Boston College’s Office of International Programs, wrote in a statement. “We have been in contact with the students and their parents and remain in touch with French officials and the US Embassy regarding the incident.”

The suspect has not been identified by name, though a local newspaper reports that following the attack, she showed pictures of herself with burns on her body. France 3 adds that she has a criminal record for violent theft. The incident is not believed to be associated with terrorism.

Europe has recently seen a disturbing uptick of acid attacks. In London, police recorded 454 such attacks last year—nearly triple the number recorded in 2012.