أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ يَتَعَاقَبُونَ فِيكُمْ مَلاَئِكَةٌ بِاللَّيْلِ وَمَلاَئِكَةٌ بِالنَّهَارِ وَيَجْتَمِعُونَ فِي صَلاَةِ الْفَجْرِ وَصَلاَةِ الْعَصْرِ ثُمَّ يَعْرُجُ الَّذِينَ بَاتُوا فِيكُمْ فَيَسْأَلُهُمْ وَهُوَ أَعْلَمُ بِهِمْ كَيْفَ تَرَكْتُمْ عِبَادِي فَيَقُولُونَ تَرَكْنَاهُمْ وَهُمْ يُصَلُّونَ وَأَتَيْنَاهُمْ وَهُمْ يُصَلُّونَ ‏"‏ ‏.‏

It was narrated from Abu Hurairah that the Messenger of Allah (PBUH) said: "Angels come to you in succession by night and day, and they meet at Fajr prayer and 'Asr prayer. Then those who spent the night among you ascend, and He (Allah) will ask them, although He knows best: 'In what condition did you leave My slaves.' They will say: 'We left them when they were praying and we came to them when they were praying.'" Translation Not Available

Book Ref: Sunan An Nisai Book 5 Hadith 485
Web Ref:  Sunan An Nisai Vol 1 Book 5 Hadith 486