وَعَنْ أَبِي عُمَيْرِ بْنِ أَنَسٍ عَنْ عُمُومَةٍ لَهُ مِنْ أَصْحَابِ
النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: أَنَّ رَكْبًا جَاءُوا إِلَى النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَشْهَدُونَ أَنَّهُمْ رَأَوُا الْهِلَالَ بالْأَمْس ن فَأَمرهمْ أَن يفطروا وَإِذا أَصْبحُوا أَن يَغْدُو إِلَى مصلاهم
Abu Umair ibn Anas told on the authority of some of his paternal uncles who were companions of the Prophet (sallallahu alayhi wa sallam) that some men came riding to the Prophet (sallallahu alayhi wa sallam) and testified that they had seen the new moon the previous day. He therefore commanded the people to break the fast and go out to their place of prayer in the morning. Abu Dawud and Nasai transmitted it.
Mishkat al-Masabih 1373, Book 5, Prayer, Hadith 851. 1 min read