The homepage of the @KuKluxKlanUSA Twitter page says: “Under anon control as of 16 NOV 2014 09:11:47. You should’ve expected us.” and features a message from Anonymous:

As well as other bizarre tweets:
The hackers also released a YouTube video about their recent takeover.

“We are not attacking you because of what you believe in as we fight for freedom of speech,” a statement below the video reads.

“We are attacking you because of what you did to our brothers and sisters at the Ferguson protest on the 12th of November.”

The KKK had recently threatened to use ‘lethal force’ during protests in Ferguson, Missouri, surrounding the August police shooting of an unarmed black teen.

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“The good people of St Louis County of all races, colours and creeds will not tolerate your threats of violence against our police officers, their families and our communities,” a flyer allegedly distributed by the Klan asserts.

“We will use lethal force as provided under Missouri law to defend ourselves.”

The threats come ahead of a grand jury decision about whether white police officer Darren Wilson will be charged in the fatal shooting of 18-year-old black man Michael Brown in the St. Louis suburb of Ferguson.

State of emergency declared in Ferguson

Missouri’s governor declared a state of emergency on Monday and activated the National Guard state militia ahead of the decision.

Governor Jay Nixon said the National Guard would assist police in case the grand jury’s decision leads to a resurgence of the civil unrest that occurred in the days immediately after shooting.

“My hope and expectation is that peace will prevail,” Nixon said.

“But we have a responsibility — I have a responsibility — to plan for any contingencies that might arise.”

There is no specific date for a grand jury decision to be revealed, and Nixon gave no indication that an announcement is imminent.

But St. Louis County Prosecutor Bob McCulloch has said that he expects the grand jury to reach a decision in mid-to-late November.

The grand jury is considering whether there is enough evidence to charge Wilson with a crime and, if so, what the charge should be.

If the jury issues an indictment, a separate jury will be selected to decide whether the person is guilty.

The U.S. Justice Department, which is conducting a separate investigation, has not said when its work will be completed.

Before the shooting, Wilson spotted Brown and a friend walking in the middle of a street and told them to stop, but they did not.

According to a St. Louis Post-Dispatch report based on sources the newspaper did not identify, Wilson has told authorities he then realised Brown matched the description of a suspect in a theft minutes earlier at a convenience store.

Wilson backed up his police vehicle and some sort of confrontation occurred before Brown was fatally shot. He was unarmed and some witnesses have said he had his hands up when he was killed.

Brown’s shooting stirred long-simmering racial tensions in the St. Louis suburb, where two-thirds of the residents are black but the police force is almost entirely white.

Rioting and looting a day after the shooting led police to respond to subsequent protests with a heavily armoured presence that was widely criticised for continuing to escalate tensions.

At times, protesters lobbed rocks and molotov cocktails at police, who fired tear gas, smoke canisters and rubber bullets in an attempt to disperse crowds.

Nixon also declared a state of emergency in August and put the Missouri State Highway Patrol in charge of a unified local police command.

Eventually, Nixon activated the National Guard to provide security around the command centre.

This time, Nixon said the St. Louis County Police Department would be in charge of security in Ferguson and would work with the Highway Patrol and St. Louis city police as part of a unified command to “protect civil rights and ensure public safety” in other jurisdictions.

The governor did not indicate how many National Guard troops would be mobilised, instead leaving it to the state adjutant general to determine.

Nixon said the National Guard would be available to carry out any requests made through the Highway Patrol to “protect life and property” and support local authorities.

If the Guard is able to provide security at police and fire stations, then more police officers may be freed up to patrol the community, Nixon said.

St. Louis Mayor Francis Slay said on Monday that he supports Nixon’s decision to activate the Guard.

He said the Guard “will be used in a secondary role” and could potentially be stationed at places such as shopping centers and government buildings.