لسان الدين بن الخطيب
Yusuf was assassinated whilst praying in Granada's Great Mosque on 19 October 1354 (Eid al-Fitr/1 Shawwal 755 AH). A man stabbed him with a dagger during the last prostration of the Eid prayer ritual. Ibn al-Khatib was present—likely praying a few metres from the Sultan, given that he was then a high court official—and his works include a detailed narration of the events. The attacker broke from the ranks of the congregation and went towards the Sultan. His movement was not noticed or did not alarm anyone because of his condition and rank, and upon reaching the Sultan, he leapt and stabbed him. The solemn prayer was then interrupted and Yusuf was carried to his royal apartment in the Alhambra, where he died. The assassin was interrogated, but his words were unintelligible. He was soon killed by a mob. His body was burnt (according to Ibn al-Khatib, though this statement might have referred to his supposed burning in hellfire) or "cut into a thousand pieces" (according to Ibn Khaldun).