The Harvard student who issued a bomb threat to skip a final test was arrested on Tuesday and held overnight by FBI agents.

20-year-old Eldo Kim, who reportedly sent in a bomb threat that caused multiple buildings on campus to evacuate, is being charged with sending a federal bomb hoax, and will make his first US District Court appearance on Wednesday, according to a representative from U.S. Attorney Carmen M. Ortiz's office who spoke with the Boston Globe.

Kim reportedly e-mailed Harvard police, university officials and the school newspaper at around 8:30 a.m. on Monday with word of "shrapnel bombs" hidden in four different buildings.

"[Be] quick for they will go off soon," the message read. Kim reportedly told FBI agents that he'd used the word "shrapnel" because he thought it carried more dangerous connotations.

Three buildings were evacuated after news of the threat spread to administrators. Students and staff in Emersen, Sever and Thayer halls, in addition to a Science Center nearby, were moved to safety at about 9 a.m., as final exams started.

According to an affidavit submitted by the FBI and obtained by the Boston Globe, Kim took on a temporary email and IP address to send the message. In the subject line, he allegedly wrote, "bombs placed around campus."

FBI agent Thomas M. Dalton said that he met with a campus police officer to speak with Kim in his dorm room Monday night, whereupon the Harvard student admitted to writing the threat.

After choosing the building of his exam, Emerson Hall, along with three others as the site for the bomb, Kim said he then walked to his test.

"According to Kim, upon hearing the alarm, he knew that his plan had worked," Dalton wrote.

According to federal law for bomb hoaxes, Kim could receive up to five years in prison, a $250,000 fine and three years of monitored release, if he's convicted.