The terrifying threat was sent to a mosque by a previously unheard of group who call themselves the ‘Christian State’.

It warned “no mosque and none of your businesses will be safe” as it threatened that “brothers [Muslims] will be slaughtered and crucified”.

The document was delivered to the Attadamoune Mosque in Molenbeek, Belgium, and found by Jamal Habbachich, one of the areas Muslim leaders and president of a local mosque association.

But Muslims across the world have publicly condemned the evil terror group as they branded it “un-Islamic and inhuman” and said its practices showed it had “no relation with Islam”.

Mr Habbachich has now directed the letter from the ‘Christian State’ to the attention of the authorities.

He said: “We will turn to the authorities of our country and complain to the police, naturally.

"Because there are two situations when you receive this kind of letter: it is a document written by someone wacky unbalanced, or it's a very serious threat.

“What also concerns me is the name of the author of the letter which we do not know, and who uses similar terminology to that of the Islamic state (ISIS).”

Mr Habbachich added he was also concerned about an increase in attacks against Muslims.

He said: “This letter is one of the elements. In the current climate, with fear in everyone’s minds, it is disturbing.”

Two other mosques in the region are also said to have received similar threats.

The shocking letter came just one week after Belgian Prime Minister Charles Michel said the government may close “certain radical mosques” in the Molenbeek district.

Belgian capital Brussels was on a lockdown last week as police carried out a number of raids amid fears of Paris copycat terror attack.

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