Valmiki Ramayana Aranya Kanda Sarga 45 Shloka 18
Original Shlokaकृतवैराश्च वैदेहि वयमेतैर्निशाचरैः।।3.45.18।। खरस्य निधनादेव जनस्थानवधं प्रति।
1 source checked for this shloka
वैदेहि Vaidehi, खरस्य Khara's, निधनादेव since his killing, जनस्थानवधं प्रति towards killing of the residents of Janasthana, वयम् we, एतैः by these, निशाचरैः by the demons, कृतवैराः developed enmity.
O Vaidehi since the killing of Khara and the residents of Janasthana we have developed enmity with the demons.