The University of Texas at Austin president said evacuating campus buildings 15 minutes before a bomb threat was to be executed left enough time for students and staff to get to safety.
School President Bill Powers said everyone was safe about 10 minutes after the evacuation order was given at 9:50 a.m. Friday. The order to clear campus buildings came 75 minutes after authorities say the threatening call was made.
Buildings were ordered evacuated at 9:53 a.m. after the university received a call from a man with a middle eastern accent claiming to be with Al Qaeda placed bombs all over campus. He said the bombs would go off in 90 minutes.
Powers said officials couldn't determine the credibility of the threat before deciding the "prudent thing" was to clear all buildings. Authorities said they were searching for bombs in the meantime.
Jessica Jimenez, a native of San Antonio who works at UT, said she was in a meeting on campus when word of the evacuation came down.
"The first thing that I noticed was the campus siren going off, very loud, and very easy to detect," she said.
Moments later, the university's emergency notification system kicked in.
"The text message basically said 'evacuate buildings and get as far away from campus as you can,'" she said.
Jimenez then joined thousands of students and faculty into rainy campus streets.
The all-clear was given at about 11:30 for people to re-enter the campus, although classes were cancelled for the day.
Here is what people said about the threat on social media.
In Fargo, North Dakota, officials at North Dakota State University ordered the campus evacuated after receiving a bomb threat.
NDSU issued a statement shortly before 10 a.m. Friday telling all employees and students to leave campus within a half-hour because of a bomb threat. No other details were given.
It is not known if the two threats were related.