daniel douglas' friend immediately alerted police. >> he was very scared about it and knew he had to something to the attention of the authorities. >> we have no reason to believe that song was acting in concert with anyone. he was acting alone. >> reporter: authorities saw it as no joke. they traced him through the internet and then to campus. >> this was no easy feat. surveillance was set up. when mr. song's vehicle came back on campus, it was followed through our extensive camera network and plain clothes officers. >> reporter: his roommate told authorities he's been stressed. police say he told their officers the same thing one week ago after they responded to a disturbance at his dorm. >> i mean, it's scary. you hear about it happening around schools across the country. >> reporter: he is charged with a misdemeanor, that carries up to $2500 in fines and six months behind bars. >> police tell wjz they did not immediately alert students of the threat because they didn't want to tip off the suspect. >>> the smell of smoke grounds a plane. the delta flight had just taken off when pa

daniel douglas' friend immediately alerted police. >> immediately he was like very scared about it and just knew that he had to bring something to the attention of the authorities. >> we have no reason to believe mr. song was acting in concert with anyone, that he was acting alone. >> reporter: authorities saw it as no joke they traced song through the internet and then to campus. >> this was no easy feet, surveillance was set up, when mr. song's vehicle came back on to campus it was followed not only through our extensive camera network but plain closed officers as well. >> reporter: song lives here in fulton and howard county we were unsuccessful reaching his family one neighbor told us she is satisfied with the way the school handled the incident. song is currently under going a psychiatric evaluation his roommate told authorities he has been stressed police say he told officers the same thing one week ago after they responded to a disturbance at his dorm. >> there was nothing that led us to believe he was a threat to himself or others. >> sounds like an isolated incident already ta