The University of Texas at Austin and North Dakota State University have reopened their campus after bomb threats -- issued around the same time -- prompted each to evacuated campus buildings.

Campus buildings at both universities were cleared, but no bombs were found. UT Austin has canceled classes for the day but says buildings can be re-entered starting at noon.

Update at 2:03 p.m. ET: When the decision was made to evacuate buildings at UT-Austin, the university sent out texts to the approximately 69,000 users signed up to its alert system, directing them to evacuate buildings, UT Police Chief Robert Dahlstrom says. University officials also sounded the on-campus siren and sent out notices via email and Facebook, he says, USA TODAY's Rick Jervis reports.

Update at 1:55 p.m. ET: North Dakota State University has lifted its evacuation order, the AP reports. The university says is will reopen campus at 1 p.m. CDT and classes will resume at 2 p.m. It says university police will spend the next hour unlocking university buildings.

FBI spokesman Kyle Loven says the agency is trying to determine whether the bomb threats to the two universities are related.

Update at 1:17 p.m. ET: The UT police chief says the threat was given for "several buildings."

Update at 1:12 p.m. ET: William Powers, president of the University of Texas at Austin, says in a tweet:

We had a threat of explosives of campus. This threat was given for later in the morning. We thought prudent to clear bldgs.

Update at 1:07 p.m. ET: North Dakota State University President Dean Bresciani says 20,000 people were evacuated from his school's main and downtown campuses in Fargo. Officials did not immediately release details about the North Dakota threat, the Associated Press reports.

Update at 1:03 p.m. ET: The University of Texas at Austin, on its website, says classes on the main university campus are canceled for the remainder of the day, but that university buildings may be re-entered starting at noon today. All university activities except for scheduled classes will resume at 5 p.m, the university says.

Update at 12:59 p.m. ET: The University of Texas says all Austin campus buildings will re-open at noon after bomb threat, the AP reports..

Update at 12:46 p.m. ET: "From what I understand, all the buildings are cleared of anything suspicious," says Lee Clippard, a UT-Austin spokesman. "All the buildings are going to be available to be re-entered at noon.(CDT) All operations are going to be resumed at 5 p.m. (CDT.)"

Update at 11:56 a.m. ET: "We have emptied the buildings and we have told folks to stay far away," Tara Doolittle, a UT-Austin spokeswoman, tells USA TODAY's Sharon Jayson. "No decision has been made on whether to hold afternoon classes. We're working with local and federal law enforcement to ensure that the campus is secure."

Doolittle says officials hope to have an update in the next couple of hours. "Once we know the buildings are secure and there's a secure place, we'll hold a press conference."

Update at 11:48 a.m. ET: According to the ValleyNewsLive.com, from Fargo, N.D., the university set out this alert on its website:

"This is an emergency message from North Dakota State University. NDSU is requiring all employees and students to leave campus by 10:15 a.m. This includes residence hall students, who, if necessary, should walk to locations off campus. This also includes the downtown buildings and agricultural facilities. NDSU received a bomb threat, prompting this evacuation. Updates will follow. "

Update at 11:45 a.m. ET: The University of Texas at Austin says on Twitter: "Buildings being checked/cleared. Stay away from buildings. No decision on afternoon classes/activities. Next update at 10:45am."

Update at 11:41 a.m. ET: "NDSU is requiring all employees and students to leave campus by 10:15 a.m.," the NDSU alert reads, according to the Star-Tribune reports. "This includes residence hall students, who, if necessary, should walk to locations off campus. The university is located in Fargo, N.D.

Update at 11:39 a.m. ET: Officials at UT-Austin say no bombs have been found.

Update at 11:31 a.m. ET: North Dakota State U. orders all employees, students off campus after receiving bomb threat, the Associated Press reports.

Update at 11:14 a.m. ET: KXAN-TV reports that the university's Director of Communications, Rhonda Weldon, says the university got a call around 8:35 a.m. local time from a male with a Middle Eastern accent claiming to have placed bombs all over campus.

The caller claimed to be from the al-Qaeda terrorist organization and that the bombs would go off in 90 minutes, KXAN reports.

President William Powers has been notified, and officials are now evacuating all of the buildings out of an abundance of caution.

Update at 11:12 a.m. ET:A UT official tells the American-Statesman that the university had received multiple bomb threats to multiple buildings.