The ruins may represent the oldest known European Christian church in the tropics.
The 400-year-old box was too damaged to be opened, but X-rays revealed a small treasure within.
There are reasons to be skeptical that a mass shooter in Oregon targeted Christians.
Fragments of red-colored plaster suggest the church walls had been decorated with frescoes.
A 1,500-year-old fragment of Greek papyrus with writing that refers to the biblical Last Supper may be one of the oldest Christian amulets.