Husayn narrates from Abu Malik al-Ghifari (may Allah be pleased with him) that he said: The Messenger of Allah (peace and blessings be upon him) offered the funeral prayer over the slain of Uhud ten at a time, and in every ten the tenth was Hamzah (may Allah be pleased with him), until he (peace and blessings be upon him) had offered the funeral prayer over him seventy times.
This is the most authentic report on this subject, and it is mursal.
Ata' narrates from al-Sha'bi that on the day of Uhud the Prophet (peace and blessings be upon him) offered seventy funeral prayers over Hamzah (may Allah be pleased with him); he began with the funeral prayer of Hamzah (may Allah be pleased with him), then he (peace and blessings be upon him) would call for the other martyrs and offer their funeral prayers, while Hamzah (may Allah be pleased with him) remained in the same place.
This too is munqati' (broken), whereas the hadith of Jabir is connected, and his father was among the martyrs of Uhud.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6804