Sayyiduna Jabir (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "A slave who dies while he is a runaway will enter Hell, even if he is killed in the path of Allah."
Al-Tabarani recorded it in al-Mu'jam al-Awsat; its chain contains a narrator, Abdullah bin Muhammad bin Aqil, whose hadith is hasan (good), though there is weakness in him; the rest of its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب العتق / 7241