Musannaf Ibn Abi Shayba 3:5800

Abu Bakr ibn Ayyash and Abu al-Ahwas narrated to us, from Abu Ishaq, from Harithah ibn Wahb al-Khuza'i, who said: I prayed with the Prophet, may Allah bless him and grant him peace, at Mina, when the people were at their most secure and when the people were most numerous, two rak'ahs.