ENOfficial
It was narrated that Anas bin Malik said: "A Bedouin urinated in the Masjid, and the Prophet (ﷺ) ordered that a bucket (be brought) and poured over it."
Source: sunnah.com
Other translations
Arabic
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا عَبِيدَةُ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ أَنَسٍ، قَالَ بَالَ أَعْرَابِيٌّ فِي الْمَسْجِدِ فَأَمَرَ النَّبِيُّ صلى الله عليه وسلم بِدَلْوٍ مِنْ مَاءٍ فَصُبَّ عَلَيْهِ .
sunnah.com