AUSTIN, Texas --
Thousands of people streamed off three college campuses Friday after bomb threats prompted officials to issue evacuation orders for schools in Texas, North Dakota and Ohio.
The campuses of the University of Texas at Austin and North Dakota State University in Fargo had been deemed safe by early afternoon, and authorities were working to determine whether those threats were related. A third evacuation order for much-smaller Hiram College in northeast Ohio was issued hours later but lifted Friday night after a sweep found nothing suspicious.
The threats on the campuses in Texas and North Dakota ended as false alarms after tens of thousands of people followed urgently worded evacuation orders, one of which some worried didn't come fast enough.
Both of those campuses emptied at quick but orderly paces Friday morning, though students acknowledged an air of confusion about what was going on. The threats coming as violent protests outside U.S. embassies in the Middle East also stirred nervous tension among some students, and Texas officials acknowledged global events were taken into account.
The first threat came around 8:35 a.m. to the University of Texas from a man claiming to belong to al-Qaida, officials said. The caller claimed bombs placed throughout campus would go off in 90 minutes, but administrators waited more than an hour before blaring sirens on the campus of 50,000 students and telling them to immediately "get as far away as possible" in emergency text messages.
Authorities said they started searching buildings for explosives before the alert was issued. UT President Bill Powers defended the decision not to evacuate sooner.
"It's easy to make a phone call ... the first thing we needed to do was evaluate," Powers said. "If the threat had been for something to go off in five minutes, then you don't have the time to evaluate, you just have to pull the switch."
Not everyone agreed.
"What took so long?" student Ricardo Nunez said. "It should have been more immediate."
North Dakota State University President Dean Bresciani said about 20,000 people left the Fargo school's campuses as part of an evacuation "that largely took place in a matter of minutes." FBI spokesman Kyle Loven said NDSU received a call about 9:45 a.m. that included a "threat of an explosive device."
Police and school officials said the evacuation was as organized as could be expected, with one campus employee describing people as "being North Dakota nice" while driving away.
"Nobody was panicked and nobody was trying to speed or run over anybody," said Juleen Berg, who works at the NDSU heating plant. "Everybody was waiting their turn."
Graduate student Lee Kiedrowski of Dickinson, N.D., said he was walking on the NDSU campus when he got a text message telling him to evacuate within 15 minutes.
"The panic button wasn't triggered quite immediately," Kiedrowski said. "But there was definitely the thought that we live in a different world now, and with everything that's going on with the riots at the U.S. embassies in the Middle East, your brain just starts moving. You never really know what's going on."
The UT president acknowledged officials in Texas also considered the current political climate.
"Certainly the global situation would be part of what we look at when we evaluate any threat," Powers said.
Hiram college received an emailed bomb threat about 4 p.m. and ordered everyone on campus to evacuate. Hiram spokesman Tom Ford said safety teams with bomb-sniffing dogs checked "room by room, building by building" on campus, which is about 35 miles southeast of Cleveland where about 1,300 students are enrolled.
The campus was deemed safe and reopened about six hours later. Ford said the college was fortunate the threat came in late evening, when many students were getting ready for the weekend.
"A lot of kids just piled into their friends' cars and were out of here," he said.