An 18-year-old college student has been missing for two weeks, since the day her family dropped her off at a train station to return to her Chicago campus.

ABC News reports that Shalyha Ahmad, a student of the University of Illinois in Chicago, has not been seen since December 14, when he family reportedly dropped her off at a train station in Chicago. The family went to the college campus later that same evening to pick her up, but she wasn’t there.

“She didn’t arrive at our meeting place and that’s when we really got worried,” the missing teen’s mother, Shetti Ahmad, said at a press conference Wednesday. “We waited around, but she never arrived and that’s when we called the police.”

The family reported Shalyha missing and police launched an investigation on December 16. So far, there appear to be very few leads and authorities are unclear on the cause of her disappearance. Investigators are “unable to determine at this time whether it is foul play or not,” a Chicago police official told ABC News.

Shalyha has not responded to any messages on social media, and her phone is not working. At the press conference, her mother said that a student at the university reported seeing Shalyha on campus that day, later in the morning after her parents dropped her off at the train station.

“We found out that she was able to get to school and that she didn’t disappear at the station.We are trying to reach some of her friends but we haven’t heard anything from them.”

“I’m just trying to appeal to all the people to help us finding our daughter,” Shetti Ahmad said. “Any information would really help us. We are really worried about her at this point. Call us or call 911 or call the TV stations, if you have any information.”