من لا يحضره الفقيه, volume 2, page 441

Hadith.2916 - Ali ibn Ri'ab narrated from Burayd al-‘Ijli, who said: I asked Abu Ja'far (as) about a man who set out for Hajj with his camel, provisions, and expenses, but died on the way. Imam (as) said: "If he was a ṣarūra (someone who had not performed the Hajj of Islam) and died within the haram, it suffices as the Hajj of Islam. If he died as a ṣarūra before entering into Ihram, his camel, provisions, expenses, and all that he had with him should be used to fulfill the Hajj of Islam on his behalf. If there is anything left over, it goes to his heirs, provided he had no debts." I asked: "What if the Hajj was voluntary, and he died on the way before entering into Ihram? What happens to his camel, expenses, and belongings?" Imam (as) said: "Everything he had and left behind goes to his heirs unless he had debts, in which case they are paid from his estate. If he left a will, it is carried out for the person he designated, with the will being fulfilled from one-third of his estate."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.