It was a tense day on the Campus of Middle Tennessee State University on Thursday as school authorities identify what they term a "credible threat".

MTSU President Sidney McPhee sent out a message Thursday saying that classes were canceled until after the fall break.

He cited a "credible threat" had been identified and for safety and security reasons, classes were canceled.

Three suspicious fires were set and threatening e-mails have been received threatening bodily harm to the students and staff at the University which is 30 miles southeast of Nashville in Murfreesboro.

Officials held a press conference late Thursday afternoon and MTSU Police Chief Buddy Peaster said "This e-mail was very generic and did not mention any particular person by name or a particular location other than the university as a whole."

Police began the process of tracking down the origination point of the e-mail as well as investigating a fire at Miss Mary Hall on Wednesday night.

The fire department extinguished the fire quickly.

After the TBI took some school computers for analysis and the continued efforts on campus to solve the case, and arrest was made.

Justin Davis, 19, was arrested late Thursday and charged with three counts of aggravated arson and one count of act of terrorism.

Davis is a student at MTSU and is from nearby Antioch, a Nashville suburb.

He has reportedly confessed to sending the e-mails that used terms in the threats like devastation and destruction.

Davis is being held with a $500,000 bond with a court appearance set for November 25th.

Students still on campus were complimentary of the University's handling of the situation and passing the word in a quick and proper manner through text messaging and e-mails.

Davis is a freshman at MTSU where about 24,000 students live on campus.

Police plan to continue their investigation to confirm that David was acting alone.