Hadith 2421
Salim bin Abdullah narrates from his father (Sayyiduna Abdullah bin Umar, may Allah be pleased with them both) that the Prophet Muhammad (peace and blessings be upon him) used to offer voluntary prayers on his mount, regardless of which direction it was facing, and he would also offer Witr on it, but he would not offer obligatory prayers on it. The narrator named Salim states: Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) would also offer voluntary prayers at night while on his mount, even while it was moving, and Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) did not care which direction he was facing.