Police say the masked, umbrella-wielding man who smashed windows at a Minneapolis auto parts store two days after George Floyd's death has ties to a white supremacist group and specifically sought to inflame racial tensions.

According to the Minneapolis Star Tribune, Minneapolis police arson investigator Erika Christensen wrote in a search warrant affidavit filed this week that the man's actions created a hostile atmosphere and sparked a series of events that turned previously peaceful protests chaotic. She said she believed his "sole aim was to incite violence."

Minneapolis police spokesperson John Elder told NPR he is unable to comment on the investigation, which is "open and active." NPR has not seen the affidavit and is not naming the man because he has not been charged with a crime.

Video of the individual breaking the windows of an AutoZone with a sledgehammer went viral this spring, prompting speculation about the identity of the so-called "Umbrella Man."

The Star Tribune reported that the man had also spray painted "free (expletive) for everyone zone" on the doors of the store, which was later burned to the ground.

In the Twin Cities of Minneapolis and St. Paul, roughly 500 businesses were damaged or looted, with nearly 70 of them burned to the ground.

"This was the first fire that set off a string of fires and looting throughout the precinct and the rest of the city," Christensen wrote in the affidavit, according to reports. "Until the actions of the person your affiant has been calling 'Umbrella Man,' the protests had been relatively peaceful."

She also wrote that she had watched "innumerable hours" of social media videos in her search for the suspect, which was unsuccessful until a tip arrived in the police department's inbox last week.

The tipster identified the man as a Hell's Angels member, and said he "wanted to sow discord and racial unrest by breaking out the windows and writing what he did on the double red doors," reported the Star Tribune.

According to Minnesota Public Radio, community members have long suspected that outside extremists were trying to inflame tensions at demonstrations against racism and police brutality in the wake of Floyd's death, with some Twin Cities residents reporting seeing "white supremacist and other far-right imagery on vehicles that came into their neighborhoods during the protests."

While the man's face was obscured by a gas mask in the video, Christensen reportedly wrote in the affidavit that his height lines up with the video, and noted a "striking resemblance in the eye, nose bridge and brow area."

Multiple news outlets report that police also linked the man to an incident that took place in Stillwater, Minn., in June, when a group of men wearing white supremacist garb allegedly harassed a Muslim woman who was at a malt shop with her 4-year-old daughter.

The reports also say police link "Umbrella Man" and the Stillwater incident with the Aryan Cowboy Brotherhood, a small white supremacist prison and street gang primarily based in Minnesota and Kentucky.

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