Ruwayfi ibn Thabit al-Ansari, a Companion present at Khaybar who took part in the conquest of the Levant and narrated hadith; under Mu'awiya he was appointed governor of Tripoli in 46/666. He died as governor of Barca (Cyrenaica) in 56 AH (c. 675) and was buried in today's al-Kawa quarter of Bayda, which long bore his name 'Sidi Rafi.' The tomb and mosque stand and are open to visitors. (Sources: classical tabaqat; Wikipedia.)