A horrific attack rocked Boulder, Colorado, on Sunday, leaving multiple people injured, some critically, after a suspect allegedly hurled Molotov cocktails at participants in a pro-Israel walk.

The FBI has classified the incident as a "targeted terror attack," while local police urge caution in speculating on the motive.

The suspect, described as a white adult male, is in custody, and authorities are intensifying their investigation into what appears to be an antisemitic hate crime occurring on the eve of the Jewish holiday Shavuot.

The assault occurred at approximately 1:26 PM MT at the intersection of 13th and Pearl Streets, a bustling pedestrian mall in downtown Boulder.

Witnesses say a shirtless man, shouting, “We have to end Zionists” and “How many children have you killed?” threw incendiary devices at a group of approximately 30 participants, setting some on fire, in the Run for Their Lives walk, a weekly event to raise awareness for Israeli hostages held by Hamas since the October 7, 2023, attack on Israel.

The assailant was also captured on video yelling, "They are killers," directed at the crowd before and after the attack.

At least six victims, aged between 67 and 88, suffered burn injuries, with some in critical condition.

Eyewitness Brooke Coffman described a chaotic scene to NBC, reporting that one woman’s hair was completely singed off, and others were seen rolling on the ground to extinguish flames.

"I saw a big fire go up,” Coffman said, noting victims stripping off burning clothes to reveal severe burns on their legs.

Miri Kornfeld, a Run for Their Lives organizer, described the scene as "the floor burning beneath them," with five people burned, including an elderly woman whose clothes caught fire.

Another witness, Johanna Schmidt, told the Times-Call that her father sustained a second-degree burn to his leg, describing the scene as “absolutely horrific and shocking."

Emergency responders rushed victims to local hospitals, including UCHealth University of Colorado Hospital in Aurora, which confirmed receiving two patients.

The attack reportedly prompted the evacuation of the 1200, 1300, and 1400 blocks of Pearl Street, with police cordoning off the area and identifying a "vehicle of interest" at the scene.

Boulder Police Chief Stephen Redfearn confirmed that a suspect was apprehended at the scene without incident and was taken to a hospital for minor injuries.

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The suspect, described as a white adult male, has not been publicly identified as of the latest updates.

Video footage circulating on social media shows a shirtless man holding glass bottles, believed to contain flammable liquid, being detained by police near the Boulder County Historic Courthouse.

The Boulder Police Department has not released further details about the suspect’s identity or background, citing the ongoing investigation.

However, Chief Redfearn emphasized that a motive has not been established, stating, "It would be irresponsible for me to speculate on motive this early on."

The FBI, in contrast, has taken a firm stance, with Director Kash Patel and Deputy Director Dan Bongino labeling the incident as ideologically motivated violence.

"This act of terror is being investigated as an act of ideologically motivated violence based on the early information, the evidence, and witness accounts," Bongino declared. "We will speak clearly on these incidents when the facts warrant it. All of the necessary assets will be dedicated to this investigation. If you have any investigative tips please contact the FBI. And if you aided or abetted this attack, we will find you. You cannot hide."

The FBI’s Denver field office, in collaboration with the National Counterterrorism Center and local law enforcement, is leading the investigation.

All upcoming Run for Their Lives events have been canceled until further notice.

Leo Terrell, head of the Justice Department’s antisemitism task force, condemned the attack, warning, "This was not an isolated incident. This antisemitic terrorist attack is part of a horrific and escalating wave of violence targeting Jews and their supporters simply for being Jewish or standing up for Jewish lives."

He noted the timing, on the eve of Shavuot, a Jewish holiday celebrating the giving of the Torah, as “chilling and cruel.”

Israel’s Foreign Minister Gideon Sa’ar described the incident as “pure antisemitism.

President Donald Trump has been briefed on the incident, according to a senior White House official.

Boulder Police reported that helicopters circling the scene are hindering drone investigations, urging the public to avoid flying aircraft over the area. A vehicle of interest is under scrutiny, though its connection to the suspect remains unclear.

The timing of the attack, coinciding with Shavuot, has amplified fears within the Jewish community following a surge in antisemitic incidents across the U.S., including the fatal shooting of two Israeli Embassy staffers in Washington, D.C., last month and an arson attack on Pennsylvania Governor Josh Shapiro’s residence in April.

The investigation remains active, with the evacuated area of Pearl Street still cordoned off.