FERGUSON, Dec 3 — The stepfather of Michael Brown, the black Missouri teenager whose August killing by a white policeman led to protests across the US, is under investigation, regarding whether his comments amounted to inciting a riot.

A St. Louis County grand jury last week declined to charge Ferguson, Missouri, police officer Darren Wilson with any crime related to his fatal shooting of the unarmed Brown, 18, in an August 9 street encounter.

That decision, announced by St. Louis County Prosecutor Robert McCulloch on the evening of November 24, touched off immediate protests, riots and looting, first in Ferguson, then in the wider St. Louis-metropolitan area. The protests spread quickly to other US cities.

St. Louis County police are now investigating crimes related to the unrest including arson, robbery and destruction of property, department spokesman Shawn McGuire said yesterday in a statement. Brown’s stepfather, Louis Head, was heard in televised broadcasts exhorting those angry with the grand jury’s decision to burn down the Ferguson police headquarters.

“The statements made by Louis Head are also under investigation,” McGuire said. Results of those inquiries will be turned over to McCulloch’s office, he said.

Adner Marcelin, a spokesman for Brown family lawyer Benjamin Crump of Tallahassee, Florida, didn’t immediately respond to voice-mail and e-mail messages yesterday seeking comment on McGuire’s statement.

Facebook threats

In Seattle yesterday, federal criminal charges were unsealed against Kirkland, Washington, resident Jaleel Tariq Abdul-Jabbaar, who is accused of using his Facebook account to urge readers to kill Wilson and harm his family.

Abdul-Jabbaar, who allegedly started posting threats on August 14, just five days after Brown was shot, is charged with three counts of making interstate threats, each punishable by as long as five years in prison.

He made an initial appearance yesterday before federal Magistrate Judge Brian Tsuchida, who scheduled a bail hearing for December 5, said Emily Langlie, a spokeswoman for the Seattle US Attorney’s office.

Abdul-Jabbaar’s attorney, Assistant Federal Public Defender Kyana Givens, declined to comment on the case.

The Seattle case is US v. Abdul-Jabbaar, 14-mj-00467, US District Court, Western District of Washington (Seattle). — Bloomberg