Ibn Umar (may Allah be pleased with them both) passed by some boys who were playing kijjah; these were holes containing pieces of wood with which they played. Ibn Umar (may Allah be pleased with them both) filled them in and forbade them from it. The narrator says: They were not opened again until afterwards.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20968