The blood-soaked cloth was stolen from a L'Aquila church over the weekend, and the two teens arrested in the theft did not understand the value of the relic or remember where they disposed of it, the Italian news agency ANSA reported.
Police found the iron frame of the reliquary, the container of the relic, on Thursday and arrested the men. A third suspect is being sought.
The reliquary and a small crucifix on the altar were discovered missing Sunday morning from the church of San Pietro della Ienca in central Italy's Abruzzi region. The suspects are believed to have broken in through a side window in the sanctuary, according to a post on the church's website