OREM, Utah — The shooter who assassinated conservative activist Charlie Kirk and then vanished off a roof and into the woods remained at large more than 24 hours later Thursday as federal investigators appealed for the public’s help by releasing a pair of photos of the person believed responsible.

Investigators obtained clues including a palm print, a shoe impression and a high-powered hunting rifle found in a wooded area along the path the shooter fled. But they had yet to name a suspect or cite a motive in the killing they were treating as the latest act of political violence to convulse the United States across the ideological spectrum.

The photos of a person in a hat, sunglasses and a long-sleeve black shirt, as well as a $100,000 reward for information leading to an arrest, suggested that law enforcement thought tips from the public might be needed to crack the case. Two people who were taken into custody shortly after Wednesday’s shooting at Utah Valley University were later released, forcing officials to chase new leads on a separate person of interest they pursued Thursday.

One clue was a Mauser .30-caliber, bolt-action rifle found in a towel in the woods. A spent cartridge was recovered from the chamber, and three other rounds were loaded in the magazine, according to information circulated among law enforcement and described to The Associated Press. The weapon and ammunition were being analyzed by law enforcement at a federal lab.

The attack, carried out in a broad daylight as Kirk spoke about social issues from a university courtyard, was captured on grisly videos that spread on social media.

The videos show Kirk, a close ally of President Donald Trump who played an influential role in rallying young Republican voters, speaking into a handheld microphone when suddenly a shot rings out. Kirk can be seen reaching up with his right hand as blood gushes from the left side of his neck. Stunned spectators gasp and scream before people start running away.

The shooter, who investigators believe blended into the campus crowd because of a “college-age” appearance, fired a single shot from the rooftop where they were perched before jumping off.

“I can tell you this was a targeted event,” said Robert Bohls, the top FBI agent in Salt Lake City.

Trump, who was joined by Democrats in condemning the violence, said he would award Kirk the Presidential Medal of Freedom, the highest civilian honor in the U.S., while Vice President JD Vance and his wife, Usha, were set to visit with Kirk’s family in Salt Lake City. Vance posted a remembrance on X chronicling their friendship, dating back to initial messages in 2017, through Vance’s Senate run and ultimately praying after hearing of the shooting.

“So much of the success we’ve had in this administration traces directly to Charlie’s ability to organize and convene,” Vance wrote. “He didn’t just help us win in 2024, he helped us staff the entire government.”

Kirk’s casket was to be flown aboard Air Force Two from Utah to Arizona, where his his nonprofit political youth organization, Turning Point USA, is based.