Updated at 2:00 p.m. ET
The University of Texas at Austin said students could return to buildings on its main campus at noon on Friday after evacuating due to bomb threats received in the morning. The school's website said that the remainder of Friday classes were canceled but other activities scheduled on the campus will resume at 5 p.m.
In addition to searching the campus, university President Bill Powers said at a news conference, "We are working very closely with city, state and federal authorities and there is a lot of information that comes from that. We are very confident that the campus is safe."
A second large college, North Dakota State University in Fargo, also was evacuated for a bomb threat, but reopened hours later.
NDSU students and employees were ordered to leave the campus by 10:15 a.m. after the school received the threat, ValleyNewsLive.com reported. Police reopened the school about 3 hours later and said classes would resume at 2 p.m.
It was unclear if there was any connection between the two bomb threats.
The University of Texas' evacuation was prompted by a call at around 8:35 a.m. from a male with a Middle Eastern accent claiming to have placed bombs all over campus, director of communications Rhonda Weldon told NBC affiliate KXAN.com. He claimed to be with al-Qaida and said bombs would go off in 90 minutes, the station reported.
Powers said that in assessing the threat with authorities, the global situation "was part of the evaluation."
The threats to campuses coincided with protests at U.S. diplomatic missions in several cities in Muslim-majority countries after the circulation of an offensive anti-Islam video produced by an obscure American filmmaker.
The University of Texas, one of the largest public universities in the U.S., has more than 50,000 students. NDSU has more than 14,000 students.
Meanwhile, Valparaiso University in Indiana alerted its students after receiving a vague threat through a graffiti message.
The school said the threat claimed "dangerous and criminal activity" would occur during the university's daily chapel break period Friday.
No evacuation was ordered, but the message urged students to be alert and report any suspicious activity on campus.
The FBI and local authorities searched the campus and found nothing suspicious, and a university police spokeswoman said classes and other activities would continue as planned, The Associated Press reported.
Please check back for more information on this breaking news story.
NBC News' Elizabeth Chuck and The Associated Press contributed to this report.
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