CALUMET CITY, Ill. (CBS) — About 10 people marched with the family of 15-year-old Stephon Watts Saturday, demanding sanctions against the Calumet City police officers who shot the autistic teen to death.

One of the teen’s uncles, Minister Aaron Watts, said he intended to begin sit-ins each Wednesday at the Calumet City police station, 1200 Pulaski Rd., at the approximate hour that Stephon was shot.

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“Three of the officers knew him,” he told the crowd, which included a number of anti-brutality activists.

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NAACP South Suburban chapter President David L. Lowery Jr. said he and the family are scheduled to meet March 9 with an investigator from the U.S. Department of Justice to discuss the case.

Lowery places little trust in the Illinois State Police Public Integrity Unit investigation, which began immediately after the shooting.

“It’s the code of blue,” Lowery said. “It’s difficult for the police to police the police.”

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The family’s minister, Bishop Lance Davis, said he is “angry” that state police have told the family virtually nothing about the investigation.

Another of Stephon’s uncles, Wayne Watts, said that the teen’s father, Steven Watts, is losing sleep over the shooting, which he witnessed in the basement of the Watts family home.

“It’s a nightmare he cannot get rid of, no matter how I try to talk with him,” Wayne Watts said. “He keeps saying, ‘Brother. I keep seeing the smoke. I keep seeing the smoke (from the officers’ guns).'”

Minister Watts said he is still seeking a legislator to sponsor a measure that would require all first responders in Illinois to receive training on ways to deal, without having to resort to deadly force, with persons with autism who are acting out.

The measure he seeks also would impose automatic suspension without pay if a first responder injures or kills someone known to have autism.

Calumet City Police contend that Stephon slashed at the officers with a kitchen knife. Steven Watts claims that nothing of the sort happened, and that Stephon had a butter knife that he was using to try to pry open the cabinet in which his computer had been locked for disciplinary reasons.

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Police had been called to the Watts home because of Stephon’s acting out 10 times in two years. Steven Watts has said that he had been advised to do so by local hospitals in order to obtain a police report, before seeking hospital treatment. He said he asked for one officer to come to the home to take the report, but said that Stephon had calmed down by the time police arrived and that he told them he did not need their assistance.