In statement, the state police officials say the appointment of Sheikh Kifah Mustapha as a volunteer chaplain is "being denied" following a background investigation.
Last December Illinois State Police made history by naming Mustapha the department's first and only Muslim chaplain. Sheikh Mustapha was one of seven ministers who went through chaplain orientation training in Springfield.
At the end of the training that Mustapha paid for himself, he and the other ministers all received their Illinois State Police ID cards, and bulletproof vests they are required to wear on ride-alongs and at crime scenes where they tend to victims and police needs.
At the Mosque Foundation of Chicago, where Mustapha is the top religious leader known as imam, his appointment as a state police chaplain was considered a triumph.
Early this year the website of a self-styled national security expert criticized Mustapha's police appointment saying he was committed to violent jihad and once was named an unindicted co-conspirator in a large terrorism case.
On Wednesday morning, the director of the Council on American-Islamic Relations will hold a news conference calling it shameful that the state police revoked Mustapha's chaplaincy. Other Muslim groups will announce they are suing the website operator.