Police in Minneapolis got a search warrant that ordered Google to provide account data on people who were near a protest that turned violent two days after the killing of George Floyd last year, TechCrunch reported.

The search warrant required Google to provide account data for anyone “within the geographical region” of an AutoZone store on May 27th, 2020, to police, according to TechCrunch. Photos of a protest outside that store two days after Floyd’s death showed a man in a mask smashing the store windows with an umbrella. The Minneapolis Star Tribune reported at the time that police believed the so-called “Umbrella Man” was actually a white supremacist trying to spark violence at the protest.

According to TechCrunch, a police affidavit showed Minneapolis police were seeking information about the identity of “Umbrella Man,” who they considered responsible for sparking violence at what had been peaceful protests.

Geofence warrants, also known as reverse-location warrants, allow authorities to sweep up location data from GPS, Bluetooth, and wi-fi from devices near a crime scene. They often pull in information from people who had nothing to do with the crime, and have raised privacy concerns. A Florida man who used a fitness app to track his bike rides briefly found himself a suspect in a 2019 burglary, when police used a geofence warrant. The man had unknowingly provided information about his location to Google, which placed him near the scene of the crime.

The use of geofence warrants has increased in the past several years; in 2019, Google reported the number of such warrants it had received was up 1,500 percent between 2017 and 2018, but did not provide specific numbers. The New York Times reported that Google received as many as 180 geofence warrants in one week in 2019.

A Minneapolis resident told TechCrunch he had received an email from Google informing him that information from his account was subject to the warrant and was being given to police. The man said he was filming the protest, not participating in it.

Google did not immediately respond to a request for comment on Sunday.