Austin police are searching for a person of interest in the on-campus killing of University of Texas dance and theater student Haruka Weiser.
A $15,000 reward has been offered for information leading to an arrest.
Weiser, an 18-year-old freshman from Portland, Oregon, was reported missing by her roommates late Monday morning. Her body was found in a creek Tuesday near the campus alumni center and the football stadium.
UT President Gregory L. Fenves described Weiser as a "beloved member" of the school's dance community who was "liked and admired by her classmates and respected by professors for her intelligence and spirit."
"The unthinkable brutality against Haruka is an attack on our entire family. Law enforcement is fully engaged to do everything to bring the perpetrator who committed this crime to justice," Fenves said in a prepared statement Thursday.
The Travis County medical examiner has ruled Weiser's death a homicide — but other than to say she was assaulted, Austin police would not reveal details of the attack, citing the ongoing investigation.
Weiser left the drama building between 9:30 p.m. and 9:45 p.m. Sunday and was attacked while walking to her dorm, police said Thursday.
University police began investigating when Weiser's roommates reported her missing the next morning. The Austin Police Department and Department of Public Safety joined the probe when Weiser's remains were discovered Tuesday.
Austin police said Thursday they have not identified a suspect, but do have a person of interest in mind. Authorities said a man was recorded on nearby surveillance video around the time of the attack.
Police are asking for the public's help in identifying him. They described the person in the video as a man standing about 6 feet tall and riding a red or pink women's bicycle.
"At this time, we do not know the identity of the suspect and we definitely will need the support of our community," Austin Police Assistant Chief Troy Gay said Thursday. "We know that the public will step up as they do in every case and help us identify the suspect."
During Thursday's news conference, Fenves read a statement on behalf of Weiser's family saying she was a "passionate and dedicated dancer and student" who hoped to soon perform again at the university.
"In theater and dance we care for and love for each other," said Jaelynn Blount, former classmate of Weiser's. I did know she was a lovely person inside and out. I can remember her sharing to us her love for dance and it just seemed so beautiful and passionate. She definitely is a person you never forget and although I didn't get to know her as much as I would like too. She will live in me."
In response to Weiser's slaying, the university has increased safety measures for the campus of roughly 50,000 students, including putting more university police officers on patrol.
Weiser's death is the first on-campus homicide investigation since 1966, when Charles Whitman killed 14 people and wounded 32 others while shooting from the UT Tower, according to the Austin American-Statesman.
Anyone with information about the person's identity is asked to call the Austin Police Department's Homicide Unit at 512-974-5372. The U.S. Marshal's Service, Texas Department of Public Safety and State Crime Stoppers is offering a combined $15,000 reward for information leading to the identification and arrest of the person responsible for Weiser's death.
NBC's Ari Mason contributed to this report.