WORCESTER, Mass. (AP) — A Worcester woman charged four years ago with suffocating her 13-month-old son with a teddy bear has filed a federal lawsuit against the police department and officers she says coerced her into confessing.

Nga Truong alleges malicious prosecution, false arrest and false imprisonment, intentional infliction of emotional distress and civil rights violations in her complaint.

Truong was 16 when she was accused of killing her son, Khyle, in 2008. She was held for almost three years before prosecutors dismissed a murder charge after a judge ruled her confession to police was obtained illegally.

Her lawyer said the interrogation was ‘‘psychological torture’’ and the now 21-year-old Truong was not given the option of consulting her mother or a lawyer.

Police Chief Gary Gemme tells The Telegram & Gazette (http://bit.ly/VtgYqR ) the lawsuit lacks merit.

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