An Emergency Notification System alert emptied five upperclassman dorms early Wednesday morning,… An Emergency Notification System alert emptied five upperclassman dorms early Wednesday morning, hours after Chancellor Mark Nordenberg’s house received a bomb threat.

After these threats were made, authorities said they have made progress in the bomb-threat investigation, although no arrests have been made.

David Hickton, United States Attorney for the Western District of Pennsylvania, issued a statement Tuesday saying that authorities have made “significant progress in the investigation” of the bomb threats, but he did not expand on exactly what this meant.

Rumors about suspects have been circulating the Internet on various blogs dedicated to the Pitt bomb threats, and many people have reported their findings to police.

“We thank the University of Pittsburgh students and community members for the information they have provided so far. The information has helped us to focus upon potential suspects,” Hickton said in the statement. “We encourage anyone who thinks that they may have information to continue sharing this with law enforcement.”

Pitt spokesperson Robert Hill said there has been no arrest, and the overall investigation continues. He would not comment on rumors of suspects “in order to protect the integrity of the investigation.”

“The University will not comment on its details, the identity of those who may or may not be of interest, or who may or may not have been cleared,” Hill said.

Pitt sent out an ENS alert just after 4 a.m. Wednesday emptying Ruskin Hall, Panther Hall, Oakwood Apartments, Centre Plaza Apartments and Bouquet Gardens. The threats brought the count of bomb threats on campus to 63.

Police on scene declined comment, and a University representative was not available for immediate comment.

These five threats came hours after Nordenberg’s University-owned house in Shadyside received a bomb threat Tuesday night around 10 p.m. Pitt police checked the residence in Shadyside and found nothing suspicious, according to the department’s media log.

Hill said that the bomb threat against Nordenberg is being investigated, but because it is a personal threat that is under investigation, he cannot discuss details.