A person of interest arrested shortly after a fatal stabbing in Waterloo nearly two months ago is now charged with the killing.

Martez Deroy Smith, 45, was formally charged with first-degree murder in Black Hawk County District Court on Thursday (January 29, 2015).

Smith is accused of stabbing Shawonyta "Marq" Norman, 39, during a fight outside a home on West 3rd Street on November 25, 2014. Waterloo police said Norman was stabbed multiple times and later died of those injuries at a local hospital.

According to investigators, Smith had a confrontation with Norman over a previous assault of Norman's sister. The victim and Smith had apparently been living together for four years.

Police arrested Smith on a domestic assault charge shortly after the stabbing and, at the time, called him a person of interest in the case. He has been in the Black Hawk County jail since his November 25 arrest on the unrelated charge.