By Lateef Mungin and Jackie Castillo, CNN
(CNN) — Rescue workers feverishly tried to free two young children who were trapped underground in a North Carolina home construction site Sunday night, sometimes digging in the dirt with bare hands.
But they were unsuccessful, and early Monday morning, their efforts had moved from search-and-rescue to recovery.
The children, a 6-year-old girl and a 7-year-old girl, were buried underground at the construction site in Lincoln County about 6 p.m., authorities said.
Neighbors told CNN affiliate WCNC that the children are cousins and were trapped after a wall of a basement that was under construction collapsed, neighbors said.
“Due to the location of the incident, which is below ground, the initial rescue efforts were unsuccessful in reaching the trapped children,” the Lincoln County Emergency Management said.
Firefighters, and a structural engineer was on the scene to help recover the children’s bodies, the agency said.
The rescue effort was changed to a “recovery operation” after rescuers dug in the dirt for two hours without finding the children.
“Crews on the scene will work around the clock to recover the bodies,” said Dion Burleson, a spokesman for Lincoln County Emergency Management.