Brazil’s defense ministry said in a statement that the unarmed soldiers were found on Thursday on an indigenous reservation on the Brazilian side of the border. “They presented themselves as deserters and are being debriefed to see if they were involved in a recent attack on a base in Venezuela,” a Brazilian military source with knowledge of the situation told Reuters. The source said their motive for deserting had not been established yet but he suspected they had been involved in a Dec. 22 raid on an infantry garrison in southern Venezuela.