Silsilat al-Ahadith al-Sahihah

Awn bin Abu Hujayfah narrates from his father, Sayyiduna Abu Hujayfah (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) was on a journey along with his companions. None of them (were able to wake up for the Fajr prayer and) they all slept until sunrise. The Prophet (peace and blessings be upon him) said: "(In such a case, there is no harm in the delay of the prayer because) you were like dead people; Allah, the Exalted, has now returned your souls to you (after the time has passed). (Remember that) whoever sleeps through a prayer should offer it as soon as he wakes up, and whoever forgets to offer a prayer should offer it as soon as he remembers."