Imam al-Sha'bi (may Allah have mercy on him) said: I was informed by someone who passed with your Prophet (peace and blessings be upon him) by a grave that was fallen in (or isolated), and we formed rows behind him (peace and blessings be upon him). He said: We said: O Abu Amr! Who narrated this hadith to you? He said: Abdullah bin Abbas (may Allah be pleased with them both).
In the narration of Wahb: I was informed by someone who saw the Prophet (peace and blessings be upon him) come to a grave that was set apart; then he led them in prayer and acted as their imam. I said: Who narrated this to you? He said: Ibn Abbas (may Allah be pleased with them both).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6999