Brihat Parashara Hora Shastra
मारकग्रहसम्बन्धान्निहन्ता पापकृच्छनिः । अतिक्रम्येतरान् सर्वान् भवत्यत्र न संशयः ॥ ९॥
Should Śani be ill-disposed and be related to a Marak Grah, he will be the first to kill in preference to other Grahas.
english translation
mArakagrahasambandhAnnihantA pApakRcchaniH । atikramyetarAn sarvAn bhavatyatra na saMzayaH ॥ 9॥
hk transliteration by Sanscript