Facebook/Getty ISIS has posted letters threatening to decapitate people in Sweden

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Bloodthirsty Daesh Islamists posted notes through the doors of dozens of random neighbours in several cities across Sweden, including the capital Stockholm, threatening to murder "non-believers" in a terrifying campaign of violence. Sweden is now on lockdown after the chilling letters pledged to behead innocent civilians and then "bomb your rotten corpses afterwards".

Intelligence officials confirmed they are investigating the horrifying threats - which were signed by "ISIS" - as a state of fear gripped the nation. The notes, written in Swedish, order people to convert to Islam or pay a religious tax, known as the jizya, warning that the police "will not save you from being murdered".

Facebook The letter, posted on Facebook, features the flag of ISIS

Facebook It warns Swedes they must convert to Islam or face being beheaded

They state: "In the name of Allah, the merciful, full of grace. You who are not believers will be decapitated in three days in your own house. We will bomb your rotten corpses afterwards. "You must choose between these three choices: 1. Convert to Islam. 2. Pay the jizya [religious tax] for protection. 3. Or else, you will be decapitated. "The police will not prevent or save you from you being murdered. (Death comes to all of you)."

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You who are not believers will be decapitated in three days in your own house ISIS letter

An image of the chilling message was posted on Facebook by one of the recipients. Swedish police said they were posted through residents' doors in a number of cities including Ronneby, Sigtuna, Västerås and the capital Stockholm, earlier this week. Local news outlets reported two Muslim asylum seekers of Iraqi origin - one in Ronneby and one in Vstroes - were amongst the recipients of the cruel letter. Sigtuna police chief Emile Anderson said officers were unsure whether or not the threats contained in the messages were real, but said they were taking them seriously. He added officials from the Swedish intelligence service Säpo are investigating the incident, according to RT Arabic.

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