(STMW) — The boyfriend of a Chicago woman found strangled in a south suburban waterway in 2009 is now charged in her death, authorities announced Wednesday.

Akira Sims, 37, was found dead in the Little Calumet River in Dolton after she was reported missing on April 4, 2009, according to a statement from Illinois State Police. Family members last saw her days before on March 26.

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An autopsy found she was strangled and ruled her death a homicide, the medical examiner’s office said.

Investigators later learned Sims had been with her boyfriend, Tyrik Knight, before she was reported missing, the statement said.

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Knight, 31, of the 13800 block of South Atlantic Avenue in Riverdale, has since been arrested and charged with one count of first-degree murder, according to state police and court records.

“Cold cases are extremely hard to solve, but every homicide investigation remains open and is a priority for the Illinois State Police’s Cold Case Unit until we solve the case,” ISP Director Hiram Grau said.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)