Narrated Anas bin Malik:

(The tribes of) Ril, Dhakwan, 'Usaiya and Bani Lihyan asked Allah's Apostle to provide them with some men to support them against their enemy. He therefore provided them with seventy men from the Ansar whom we used to call Al-Qurra' in their lifetime. They used to collect wood by daytime and pray at night. When they were at the well of Ma'una, the infidels killed them by betraying them. When this news reached the Prophet , he said Al-Qunut for one month In the morning prayer, invoking evil upon some of the 'Arab tribes, upon Ril, Dhakwan, 'Usaiya and Bani Libyan. We used to read a verse of the Qur'an revealed in their connection, but later the verse was cancelled. It was: "convey to our people on our behalf the information that we have met our Lord, and He is pleased with us, and has made us pleased." (Anas bin Malik added:) Allah's Prophet ﷺ said Qunut for one month in the morning prayer, invoking evil upon some of the 'Arab tribes (namely), Ril, Dhakwan, Usaiya, and Bani Libyan. (Anas added:) Those seventy Ansari men were killed at the well of Mauna.

حَدَّثَنِي عَبْدُ الأَعْلَى بْنُ حَمَّادٍ، حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، حَدَّثَنَا سَعِيدٌ، عَنْ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ أَنَّ رِعْلاً، وَذَكْوَانَ وَعُصَيَّةَ وَبَنِي لَحْيَانَ اسْتَمَدُّوا رَسُولَ اللَّهِ ﷺ عَلَى عَدُوٍّ، فَأَمَدَّهُمْ بِسَبْعِينَ مِنَ الأَنْصَارِ، كُنَّا نُسَمِّيهِمُ الْقُرَّاءَ فِي زَمَانِهِمْ، كَانُوا يَحْتَطِبُونَ بِالنَّهَارِ وَيُصَلُّونَ بِاللَّيْلِ، حَتَّى كَانُوا بِبِئْرِ مَعُونَةَ قَتَلُوهُمْ، وَغَدَرُوا بِهِمْ، فَبَلَغَ النَّبِيَّ ﷺ، فَقَنَتَ شَهْرًا يَدْعُو فِي الصُّبْحِ عَلَى أَحْيَاءٍ مِنْ أَحْيَاءِ الْعَرَبِ، عَلَى رِعْلٍ وَذَكْوَانَ وَعُصَيَّةَ وَبَنِي لَحْيَانَ. قَالَ أَنَسٌ فَقَرَأْنَا فِيهِمْ قُرْآنًا ثُمِّ إِنَّ ذَلِكَ رُفِعَ بَلِّغُوا عَنَّا قَوْمَنَا، أَنَّا لَقِينَا رَبَّنَا، فَرَضِيَ عَنَّا وَأَرْضَانَا. وَعَنْ قَتَادَةَ عَنْ أَنَسِ بْنِ مَالِكٍ حَدَّثَهُ أَنَّ نَبِيَّ اللَّهِ ﷺ قَنَتَ شَهْرًا فِي صَلاَةِ الصُّبْحِ يَدْعُو عَلَى أَحْيَاءٍ مِنْ أَحْيَاءِ الْعَرَبِ، عَلَى رِعْلٍ وَذَكْوَانَ وَعُصَيَّةَ وَبَنِي لَحْيَانَ. زَادَ خَلِيفَةُ حَدَّثَنَا ابْنُ زُرَيْعٍ، حَدَّثَنَا سَعِيدٌ، عَنْ قَتَادَةَ، حَدَّثَنَا أَنَسٌ، أَنَّ أُولَئِكَ السَّبْعِينَ، مِنَ الأَنْصَارِ قُتِلُوا بِبِئْرِ مَعُونَةَ، قُرْآنًا كِتَابًا. نَحْوَهُ.