Sunan Ibn Majah
528
Sahih+3

It was narrated from Anas bin Malik that:A Bedouin urinated in the mosque, and some of the people rushed at him. The Messenger of Allah said: "Do not interrupt him." Then he called for a bucket of water and poured it over (the urine)

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi