Investigators are still trying to unravel the case of a 29-year-old woman who allegedly lied on her birth certificate to enroll in a New Jersey high school, which she attended for four days posing as a student -- and while they said in an update this week they're unsure of her motive, they do not believe it was all nefarious in nature.

Hyejeong Shin was charged Jan. 24 with a single count of providing a false government document to the New Brunswick Board of Education with the intent to enroll in the New Brunswick High School as a juvenile student. She was issued a summons and released, and now awaits an upcoming court appearance, authorities say.

"New Brunswick police detectives will continue to explore each avenue of this investigation and better understand Ms. Shin’s motive for enrolling at the New Brunswick High School," the department said in a Wednesday update. "At this time, nothing has revealed that Ms. Shin’s intentions for enrolling in the New Brunswick High School was to bring harm or violence to the students, staff or faculty."

Why did she want to enroll, then? Many still want to know. They also want to know how she didn't get caught for days.

More than 2,000 students attend New Brunswick High School, all teenagers learning how to become adults. But police said one of those students, Shin, already was an adult. School officials said she had been going to classes, pretending to be a teenager for four days before they caught onto her and ordered her off the property.

It wasn't immediately made clear how they caught on. Students at the school told the local paper, New Brunswick Today, after Shin's arrest that she was making friends -- and once they learned she allegedly lied about her age and faked her enrollment, they said they feared she may have been trying to recruit girls for sex trafficking.

“I think she was really trying to traffic young women which is what anybody who hears about this needs to be aware of your surroundings," said Abrianna Martin, a senior at the school. "I heard she was still trying to contact some of the young girls here even after we found out."

Other teens in the neighborhood called it a terrifying prospect at the time of Shin's arrest.

“Honestly, I would be really scared," said 16-year-old Desiree Daly. "Having someone that’s not from my school or knowing anyone around me coming to school that’s older than me and talking to me, not having a good intention in my school and around my friends. It’s frightening."

School Superintendent Dr. Aubrey Johnson addressed the issue at a school board meeting, saying "certainly we have cautioned all our students, preferably those who may have encountered this person while she was in our high school."

Students were told to stop all contact with her, online or in person. The superintendent also said the district directly contacted parents of students with whom Shin was in contact.

District officials said that once they figured out they were dealing with a fraud, they called the police immediately. That said, they say they will be reviewing school policy and state law to see how they can prevent any similar occurrences.

News 4 hasn't been able to reach Shin for comment on the case. Attorney details for her weren't clear.