The bodies of four people, including a toddler and two infants, were found Sunday night along the US-Mexico border, according to cops.

Authorities in Hidalgo County, Texas, reported the grisly discovery on Twitter.

“Bodies appear to be 2 infants, a toddler and 20yoa female,” said local Sheriff Eddie Guerra around 9:35 p.m. CT. “Deputies are on scene…awaiting FBI agents who will be leading.”

The bodies were found by Border Patrol agents in the Las Paloma Wildlife Management Area, just southeast of Anzalduas Park, according to Guerra.

A cause of death was not immediately clear, but law enforcement sources told Channel 5 News that the victims showed no signs of foul play. Investigators believe they may have died from dehydration. The FBI was expected to take over the case Sunday night.