Aśvatthāmā, the murderer of the princes, seeing from a great distance Arjuna coming at him with great speed, fled in his chariot, panic stricken, just to save his life, as Brahmā fled in fear from Śiva.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
तमापतन्तं स विलक्ष्य दूरात् कुमारहोद्विग्नमना रथेन । पराद्रवत्प्राणपरीप्सुरुर्व्यां यावद्गमं रुद्रभयाद्यथार्कः
tamāpatantaṃ sa vilakṣya dūrāt kumārahodvignamanā rathena | parādravatprāṇaparīpsururvyāṃ yāvadgamaṃ rudrabhayādyathārkaḥ
SB 1.7.18