WASHINGTON: The Islamic State terror group has called for "slaughter" of American voters on Election Day and urged Muslims not to participate in the democratic process, according to a US-based terrorist monitoring group.Ritz Katz, director of the SITE Intelligence Group, said on Twitter that the threats appear in an essay carried by the Islamic State's Al Hayat media center that declares militants "have come to slaughter you and smash your ballot boxes."The warning is carried in a seven-page manifesto, entitled 'The Murtadd Vote', The USA TODAY reported.The essay, which uses lengthy religious arguments in an effort to justify such attacks, also declares there is no difference between the Republican and Democratic parties in their "policies against Islam and Muslims".Katz posted excerpts of the essay on Twitter, saying the Islamic State, also known as ISIS , was inciting attacks on Election Day "in an attempt to disrupt the election process and gain media attention."The full essay, in English, includes a photograph of Republican presidential nominee Donald Trump, Democratic vice presidential nominee Tim Kaine, as well as a photo Khizr Khan, the father of a Muslim US soldier killed in combat, holding a copy of the US Constitution during his dramatic speech at the Democratic National Convention, the report said.Regarding possible vote-related threats, federal authorities are reviewing information about al-Qaida's potential interest in conducting attacks in the US on the eve of Tuesday's elections, several federal and state law enforcement officials had said on Friday.The credibility of the threat , which identified New York, Virginia and Texas as locations, has not been established, one official told USA TODAY."The counter-terrorism and homeland security communities remain vigilant and well-postured to defend against attacks here in the United States," the FBI said in a statement.