Rex_Wholster/iStock(RIO GRANDE VALLEY, Texas) — Four bodies were found Sunday evening near the Rio Grande River, southeast of the Anzalduas Park in Las Paloma Wildlife Management Area, an area rife with human trafficking, authorities said.

The deceased appeared to be two infants, a toddler and a 20-year-old woman, Hidalgo County Sheriff Eddie Guerra told ABC News Rio Grande Valley, Texas, affiliate KRGV-TV.

Because the bodies were found on federal property, the FBI will handle the investigation.

The four people may have died from dehydration, investigators told KRGV.

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