Musannaf Ibn Abi Shayba 11:132

'Isa ibn Yunus ibn Abi Ishaq narrated to us, my father informed me, from men of Banu Salama: They said: When Mu'awiya diverted his spring which passes by the graves of the martyrs, it flooded them—meaning the grave of 'Abdullah ibn 'Amr ibn Haram and the grave of 'Amr ibn al-Jamuh. So their two graves were exposed. He called for help regarding them, so we brought them out, and they were bending [as if they were alive], as if they had died only yesterday. Upon them were two garments, and their faces were covered with them, and upon their feet was some of the vegetation of the earth.