ORONO, Maine (AP) — The University of Maine says students are being allowed return to a building that houses chemistry and marine sciences classes following a bomb threat hoax.

Spokesman Ron Lisnet says two classes with 115 students were under way when the evacuation order was given Thursday morning at . Police searched the building and declared it safe for students to return in time for five classes that were scheduled for 11 a.m.

Lisnet says the threat was made via email Wednesday night to a staff member, who saw the email Thursday morning. Police were alerted at 8:16 a.m.

The campus IT department is working with university police to sort out the origin of the email.

Copyright 2012 The Associated Press.