Authorities believed Jose Antonio Ramirez-Duran forced his way inside the victim's residence in broad daylight on June 9.
He physically assaulted her then stabbed her multiple times in the chest and neck, according to city police. Authorities said the victim's two children were home during the attack.
The 45-year-old fled before police arrived and has not been located, officials said.
Anyone with information is asked to call 610-865-7000 or email BethlehemPolice@bethlehem-pa.gov. To submit an anonymous tip, call 610-691-6660.
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