The Minneapolis Police Department’s website has shown signs of a hack since late Saturday, days after a video purported to be from the hacktivist group Anonymous promised retribution for the death of George Floyd during an arrest.

Websites for the police department and the city of Minneapolis were temporarily inaccessible on Saturday as protesters in cities around the U.S. marched against police violence aimed at black Americans.

By Sunday morning, the pages sometimes required visitors to submit “captchas” to verify they weren’t bots, a tool used to mitigate hacks that attempt to overwhelm pages with automated requests until they stop responding.

Officials with the police department and the city didn’t immediately respond to requests for comment.

Anonymous posted a video on their unconfirmed Facebook page on May 28 directed at the Minneapolis police. The post accused them of having a “horrific track record of violence and corruption.”

The speaker, wearing a hoodie and the Guy Fawkes mask that’s a well-known symbol of the group, concludes the video with, “we do not trust your corrupt organization to carry out justice, so we will be exposing your many crimes to the world. We are a legion. Expect us.”

The video was viewed almost 2.3 million times on Facebook over the weekend, during which violence swept the U.S. as protesters clashed with law enforcement and National Guard troops.

While many demonstrations have been peaceful, others have devolved into rioting. Several cities issued curfews and police have at times turned their rubber bullets and mace on the activists and on journalists covering the protests.

President Donald Trump on Sunday cast blame on the media for stoking the violence that’s followed the death of Floyd, an unarmed black man, in Minnesota police custody.

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