Narrated By ‘Aisha :
Abu Bakr asked the Prophet to allow him to go out (of Mecca) when he was greatly annoyed (by the infidels). But the Prophet said to him, ”Wait.” Abu Bakr said, O Allah’s Apostle! Do you hope that you will be allowed (to migrate)?” Allah’s Apostle replied, “I hope so.” So Abu Bakr waited for him till one day Allah’s Apostle came at noon time and addressed him saying “Let whoever is present with you, now leave you.” Abu Bakr said, “None is present but my two daughters.” The Prophet said, “Have you noticed that I have been allowed to go out (to migrate)?” Abu Bakr said, “O Allah’s Apostle, I would like to accompany you.” The Prophet said, “You will accompany me.” Abu Bakr said, “O Allah’s Apostle! I have got two she-camels which I had prepared and kept ready for (our) going out.” So he gave one of the two (she-camels) to the Prophet and it was Al-Jad’a. They both rode and proceeded till they reached the Cave at the mountain of Thaur where they hid themselves. Amir bin Fuhaira was the slave of ‘Abdullah bin Al-Tufail bin Sakhbara ‘Aisha’s brother from her mother’s side. Abu Bakr had a milch she-camel. Amir used to go with it (i.e. the milch she-camel) in the afternoon and come back to them before noon by setting out towards them in the early morning when it was still dark and then he would take it to the pasture so that none of the shepherds would be aware of his job. When the Prophet (and Abu Bakr) went away (from the Cave), he (i.e. ‘Amir) too went along with them and they both used to make him ride at the back of their camels in turns till they reached Medina. ‘Amir bin Fuhaira was martyred on the day of Bir Ma’una.
Narrated ‘Urwa: When those (Muslims) at Bir Ma’una were martyred and ‘Amr bin Umaiya Ad-Damri was taken prisoner, ‘Amir bin At-Tufail, pointing at a killed person, asked Amr, “Who is this?” ‘Amr bin Umaiya said to him, “He is ‘Amir bin Fuhaira.” ‘Amir bin At-Tufail said, “I saw him lifted to the sky after he was killed till I saw the sky between him and the earth, and then he was brought down upon the earth. Then the news of the killed Muslims reached the Prophet and he announced the news of their death saying, “Your companions (of Bir Ma’una) have been killed, and they have asked their Lord saying, ‘O our Lord! Inform our brothers about us as we are pleased with You and You are pleased with us.” So Allah informed them (i.e. the Prophet and his companions) about them (i.e. martyrs of Bir Mauna).
On that day, ‘Urwa bin Asma bin As-Salt who was one of them, was killed, and Urwa (bin Az-Zubair) was named after ‘Urwa bin Asma and Mundhir (bin AzZubair) was named after Mundhir bin ‘Amr (who had also been martyred on that day).