The shooter jumped off the roof and fled into an adjoining neighbourhood, Robert Bohls, the FBI special agent in charge, told reporters.
Investigators found a “high-powered, bolt-action” rifle in a nearby wooded area, and were examining that along with palm prints and footprints for clues.
On Thursday, with classes cancelled, the roof of the building on the otherwise deserted campus and the nearby woods were strung with yellow tape as investigators scoured them for evidence.
The shooter appears to be of college age and “blended in well” on the campus, Utah Public Safety Commissioner Beau Mason told reporters.
The shooter has not been publicly identified, though lawmakers, commentators and online sleuths have already filled social media and message boards with speculation and blame-casting about the killer’s ideology.
FBI Director Kash Patel was travelling to Orem and due to brief reporters later on Thursday, NBC News reported.
The FBI offered a US$100,000 reward for information leading to the killer’s arrest and circulated grainy images apparently taken from security cameras showing a “person of interest” wearing a black top, black sunglasses and a dark baseball cap. The top appears to have an image of a bald eagle flying across a US flag.
