Musnad Ahmad 32:2090

'Affan narrated to us, Hammad narrated to us, from Thabit, from Anas, that the Messenger of Allah (peace and blessings of Allah be upon him) used to pray towards Bayt al-Maqdis (Jerusalem). Then, "We have certainly seen the turning of your face, [O Muhammad], toward the heaven, and We will surely turn you to a qiblah with which you will be pleased. So turn your face toward al-Masjid al-Haram" [Al-Baqarah: 144] was revealed. A man from Banu Salamah passed by them while they were bowing in the dawn prayer, and they had already prayed one rak'ah. He called out, "Behold, the qiblah has been changed! Behold, the qiblah has been changed toward the Ka'bah." He said: So they turned as they were toward the qiblah.