It is narrated from Hazrat Usama (may Allah be pleased with him) that once the Holy Prophet (peace and blessings of Allah be upon him) sent him with an army to a certain direction, but during this time the Holy Prophet (peace and blessings of Allah be upon him) passed away. Hazrat Siddiq Akbar (may Allah be pleased with him) asked him, "What command did the Holy Prophet (peace and blessings of Allah be upon him) give you?" He replied, "The Holy Prophet (peace and blessings of Allah be upon him) commanded me to attack 'Abni' in the morning and set it on fire."
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 21824
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد ضعيف لضعف صالح ابن أبى الأخضر