This has been confirmed in mutawatir (continuous) reports from the Prophet, upon whom be peace, concerning his actions and statements. Ibn ‘Umar said, “The Prophet lagged behind us in one of our travels. He caught up with us after we had delayed the afternoon prayer. We started to make ablution and were wiping over our feet, when the Prophet said, ‘Woe to the heels, save them from the Hell-fire,’ repeating it two or three times.” (Related by al-Bukhari and Muslim.)
Needless to say, the preceding obligations are the ones that Allah has mentioned in (al-Ma’idah 6).