Rescue crews in North Carolina discovered the bodies of two children who were killed Sunday, April 7, when a wall of dirt collapsed on top of them according to the Charlotte Observer.

Crews were making progress in recovering the two children, a 6-year-old girl and a 7-year-old boy, but have exercised caution in order to "avoid another cave-in" according to Dion Burleson, a spokesperson for Lincoln County Emergency Management.

The children were buried under approximately 15 feet of debris in an "excavated hole" that was between 20 to 25 feet according to local authorities.

The bodies were discovered at around 6 a.m. today, April 8 after a 13 hour search.

"The children were in a dug-out portion of the area," Lincoln County Sheriff David Carpenter said according to Charlotte Observer. "There were several thousand pounds of dirt on top of them."

Carpenter also stated that the identities of the children have yet to be released, though they were able to confirm the two children were playing in the hole while the 7-year-old's father was operating a backhoe.

Police have not been able to determine what the father was building, but have allowed the family to grieve for the time being as the investigation goes forward.

The first 911 call came at 5:07 p.m. from the boy's father Jordan Caldwell according to local authorities.

It took four hours of digging with shovels and automated digging equipment. Helicopter cameras were also used to capture footage of the 20 to 30 foot pit. Officials stated that they weren't able to use heavy equipment in the hole, just in case the kids were alive.

Over 100 people were involved in the effort to dig up the two kids.

The crew members worked "as if they were alive" according to public information officer Dion Burleson.

"There are calls at times like this happen where we are not able to make a difference because it's outside of our realm," Burleson said to NBC Charlotte. "This is one of those cases, and it's devastating to not only to the family, but each and every one of the responders that is out here."

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