Investigators say Keith Smith, 25, became upset when the victim told him the baby she was carrying was not his.
Smith is currently at large.
He is described as a white man, 5'7" tall, weighing 185 pounds and was last seen wearing a black and green shirt, jeans and white sneakers.
Anyone with information on Smith's whereabouts is asked to call police at (302) 736-7111.
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