The University of Texas at Dallas briefly evacuated its campus on Tuesday afternoon after receiving a bomb threat but police later determined it was a hoax and reopened the campus.

The university tweeted at around 2:45 PM local time that all faculty, students, staff, and visitors needed to immediately leave buildings and parking garages on the campus, located roughly 29 kilometres north of downtown Dallas, in Richardson.

After the orders to leave were issued, television footage from a local Fox affiliate showed a long line of cars leaving one area of campus, and dozens of people standing around buildings and parking lots in other areas.

Campus police received the bomb threat around 2 PM local time from an anonymous caller who demanded a large amount of money, the Dallas Morning News quoted the University of Texas at Dallas Police Department Lieutenant Ken MacKenzie as saying.

Less than an hour later, university officials tweeted that campus police had determined the bomb threat was a hoax.

"We do not believe this to be a valid bomb threat," MacKenzie said, according to the Dallas Morning News. "The person hung up before we could get any details."