Police said the victim, Rosaleo Apuyan, confronted Salvador Balinis, 51, for allegedly getting the relief goods intended for his family.
A verbal tussle ensued between the two men. Balinis wife, Leoneda, 49, went to her husbands rescue and stabbed Apuyan several times, killing him on the spot.
Police collared Balinis, but his wife managed to flee their evacuation center in Barangay San Andres. Murder charges have been filed against the couple.
Apuyan and the Balinis couple were neighbors in Barangay Fidel Surtida, which is within the seven-kilometer extended danger zone around the restive Mayon Volcano.