A weekend of protests across Portland featured a series of now familiar scenes: hundreds of people blocking traffic, hurling eggs, apples and insults; police officers tackling, pepper-spraying and arresting fleeing demonstrators; and a riot declared after someone started a fire inside police union headquarters.

But early Saturday morning brought a disturbing new element: Protesters allege someone threw pipe bombs at them while they were gathered in Laurelhurst Park.

Around 2:30 am on Aug. 8, a group of legal observers and journalists, including reporter Justin Yau, met up near Laurelhurst Park, at the corner of Southeast Ankeny Street and César E. Chávez Boulevard. Abruptly, they saw a white light flash over the park's tall Douglas firs and heard an explosion, followed by a deep reverberation. The noise was much louder than the fireworks typically thrown at protests. So when a second explosion sounded, they stopped talking and ran toward the sound into the darkened park.

By the public restrooms on the park's north side, they found 20 protesters gathered around a small device, examining and dismantling it. One of the protesters explained to the reporters that the group had just evaded several thrown pipe bombs.

"Two of these were thrown at us by a gentleman who disappeared back into the woods," the protester said, asking that her name be withheld out of concern for her safety. "This is a Ziploc bag full of gunpowder, taped as tight as it can go, fit into [a PVC pipe], and the idea is that it would explode. But only one went off. This one was a dud," she said, gesturing to the dismantled contents.

"Five minutes later, one or two other gentlemen came from the dark parts of the area and threw one or two more and they exploded," she added, saying the group was lucky the first bomb was a dud because it gave them a moment to step back before the second exploded.

Other protesters in the group confirmed the account, seeming tired and shaken. The group alleged four or five explosives had been thrown in total.

In the minutes following the blasts, Portland police vehicles cruised around Laurelhurst Park but stopped short of entering it. Two cars stopped about a half-block from the alleged ambush location but departed with their lights off without questioning any witnesses or assessing possible injuries.

As of Saturday morning at 11 am, Sgt. Kevin Allen of the Portland police public information office responded to questions about the pipe bombs by saying he had "not heard about this happening." But by 7:14 pm on Saturday, a press release from the Portland Police Bureau indicated police were now investigating the incident, requesting eyewitness accounts and "remnants or unexploded material from the scene."

The release also mentions social media posts "showing a person that social media users are reporting to have been involved in this incident." This appears to refer to a video filmed by Scott Keeler, a videographer covering the Portland protests who was on the scene when the explosions occurred.

Directly following the explosion, teams of protesters pursued their alleged assailants through the park with flashlights. Keeler became separated from the group but encountered a man on a nearby side street holding a multicam tactical helmet with night vision optics. He noticed the man changed direction after noticing Keeler's flashlight.

Keeler says he'd seen the same man in Laurelhurst Park several minutes earlier, walking away from where the pipe bomb detonated. He did not film that encounter but recorded the second interaction.

"Why are you throwing pipe bombs at people?" Keeler asks in the video. He also asks about the man's "night vision goggles."

"Look man, I'm not the guy you wanna fuck with," the man in the video responds after Keeler films his face. Keeler asks again about the pipe bombs, and the man says, "I don't know what you're talking about. But I'm not that guy you wanna fuck with. I'm fucking telling you."

Interviewed after the confrontation, Keeler said the man reached behind his back at waistband level, so Keeler stopped recording and backed away.

Several protesters claimed to know the man's identity, but WW was unable to independently verify who he was.

The pipe bomb explosions could be an escalation of violence against protesters by other citizens, adding greater danger to an already unstable situation. On Aug. 3, a protester was stabbed in front of the Multnomah County Justice Center, and a truck driver accelerated toward a crowd of protesters in North Portland on Aug. 4, striking and dragging a motorcycle for several blocks.