(CNN) A 3-year-old boy was all by himself in the middle of a cornfield on the Texas border when Border Patrol agents found him Tuesday, US Customs and Border Protection officials said.

The boy was crying, and had his name and phone numbers written on his shoes. The agency tweeted out an image indicating they were still trying to reach the child's family.

"We believe the boy was with a larger group that ran when they encountered agents," the tweet says.

Early this morning, #USBP Agents found a 3-year-old boy alone and crying in a corn field in TX. He had his name & phone numbers written on his shoes. #CBP is attempting to reach his family. We believe the boy was with a larger group that ran when they encountered Agents. pic.twitter.com/0s0zwmFxih — CBP (@CBP) April 24, 2019

Irma Chapa, communications director for the Border Patrol's Rio Grande Valley Sector, said agents responded Tuesday morning to a group of migrants who had crossed the Rio Grande. The group scattered and fled back to the river, Chapa said. As agents were searching for them, they heard a child crying in a nearby field.

"Agents searched and located a sobbing toddler abandoned in the middle of the field," Chapa said. "The child appeared to be healthy and unharmed."

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