Lashawn McNeil, 47, was on probation for a 2003 drug conviction in New York City, authorities say. He also has several out-of-state arrests.
In 2002 and 2003, McNeil was arrested three times in Pennsylvania on drug charges and suspicion of assaulting a police officer.
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Authorities say he posted anti-government and anti-police material on social media.
McNeil was reportedly staying with his mother to help her take care of her other son, who has special needs.
Ex-Brit turned Manhattan resident since 2008.