Imran bin Abi Ata said: I was present with Muhammad ibn al-Hanafiyyah when Sayyiduna Ibn Abbas (may Allah be pleased with them both) died in Ta'if. He said four takbirs over him (in the funeral prayer), took hold of him from the side of the qiblah when lowering him into the grave, and kept a tent pitched over his grave for three days.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10527