The boy was “abandoned” by a group of suspected illegal immigrants who had crossed into the United States from Mexico near Brownsville, Texas, the CBP said.
“As agents attempted to intercept the group, the suspected illegal aliens scattered in the overgrown field,” the CBP said in a statement.
The boy, who was “alone and crying,” was discovered during a search of the field and taken to a local hospital, where he was found to be in good condition, it said.
Efforts to locate his family have so far been unsuccessful.
He is being taken care of at a centralized processing center and will be turned over to the custody of the Department of Health and Human Services, the CBP said.
According to the CBP, border patrol agents apprehended 92,607 people along the southwest border in March, up from 66,884 in February.
Among those apprehended in March were 8,975 unaccompanied children.
President Donald Trump said Wednesday that the United States would send armed soldiers to the southern border after Mexican soldiers recently “pulled guns” on US troops, escalating his war of words with Mexico on immigration.
Trump, who has made the immigration the core of his message to his conservative base, also said on Twitter that “a very big Caravan of over 20,000 people” is making its way through Mexico toward the United States.