AUSTIN -- University of Texas Police arrested a Crosby man they say made terroristic threats toward the university.

In a release sent on April 15, the University of Texas Police Department wrote that Sean Evan Haddon, 23, was arrested in Crosby, Texas, near Houston around 9 a.m. He was booked on the third-degree felony offense of terroristic threat.

According to the release, the first call came in on April 7 around 3:57 a.m. A person stated they were going to put a pipe bomb in the lobby of the police department. The caller wanted a $100,000 payment in bitcoin and asked the dispatcher to perform sexual acts, or he would blow up the building, according to an affidavit for his arrest. The caller identified himself as Rakish Robinson and spoke with a Middle-Eastern accent and threatened to blow up the building, police said. The call was disconnected, but another call sounding like the same person came in minutes later. Officers searched the building and found no suspicious activity or explosive devices.

Sean Evan Haddon

Then, on April 12, the UTPD 911 Communications Center received another call from someone believed to be the same person. The caller told the operator that he had shot a person the night before, cut his friend's leg off and was going to shoot the operator next, police said. He also asked that dispatcher to perform sexual acts.

Investigators then contacted internet and phone providers, who determined the calls came from Haddon of Crosby, Texas, according to the press release.

On April 13 around 11:54 a.m., an employee at the UT Human Resource Service Center reported another call. A supervisor said they were on the phone with a man who said he had a gun on campus and wanted to shoot "at least 200 people" at the university. Police said the caller also told an officer who took over the call that he would "kill the first person he sees."

A spokesperson with UTPD said police investigated each case thoroughly and determined there were no threats to the area as the suspect was found to be in Crosby.

According to the arrest affidavit, a phone provider gave police the location of Haddon's current residence.

"Once we identified where the suspect was and he was not in Austin and we knew that, we did not believe it was an actual imminent threat to the university," said UT Police Chief David Carter.

Officials said students or staff were not told to take safety precautions during this time.

"It's a little uneasy that these threats are being made and I think this is the first time I'm hearing about something where I haven't heard about it from UTPD," said Suraj Bawar, a student.

Officials said Sunday that investigation is ongoing as searches are completed. The suspect's home was cleared, though an undisclosed number of firearms and ammunition were seized. As of Sunday afternoon, police said no connections between the suspect and the Austin-area had been discovered.

Haddon has been charged with terroristic threat and his bond was set at $300,000.