At the Kirkland apartment complex where Abdul-Jabbaar was arrested, people were stunned.

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Mariam Zayas knows Abdul-Jabbaar. “It doesn't seem real because he seemed real quiet and real nice, nice guy,” she said.

“I'm shocked that someone would make a statement like that; it's just appalling,” Alexander Lash said.

Wilson's shooting of the 18-year-old Brown – and the Ferguson Police Department's response – generated outrage across the country. Chaotic protests gripped the streets of Ferguson and sparked a nationwide debate about race and law enforcement.

On Nov. 24, a grand jury decided Wilson would not be indicted for the shooting. Wilson resigned on Saturday.

According to the criminal complaint, Abdul-Jabbaar started posting threats on his Facebook page shortly after the Aug. 9 shooting of Brown and continued through late November.

People who live with Abdul-Jabbaar at his apartment complex said he never gave the impression that he cared about the controversy in Ferguson.

Wilson is currently living in an undisclosed location, which his lawyer says will be his more-or-less permanent residence. The former officer was married a few weeks prior to the grand jury decision, and the couple is expecting their first child.

– The Associated Press contributed to this report.