Sayyidah Aishah Siddiqah (may Allah be pleased with her) narrates that the Prophet (peace and blessings be upon him) said: "Being killed while bound (in captivity) does not pass by any sin except that it wipes it out."
Al-Bazzar recorded it and said: To our knowledge, this is narrated from the Prophet (peace and blessings be upon him)
only through this chain; and its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الحدود والديات / 10602