Archaeologists working in central Alaska discovered the 11,500-year-old remains of two infants from the Ice Age.

The bones, found in an ancient burial site near the Tanana River, are considered the youngest human remains found in the North American Arctic.

A team of researchers from University of Alaska at Fairbanks made the discovery in the fall of 2013 and published their findings in the Proceedings of the National Academy of Sciences journal.

Along with the infants were found weapons described as "hafted projectiles, confirming earlier conclusions about Paleoindian weapon system form and function," Ben Potter, the lead author of the paper, wrote.

"Taken collectively, these burials and cremation reflect complex behaviors related to death among the early inhabitants of North America," he added.

Michael Waters, an archaeologist at Texas A&M University, told SmithsonianMag.com the fact these items were left with the infants shows how valued the babies were.

"While the artifacts left behind were functional tools and materials need to survive, they were still left with the children. This bespeaks of the deep sense of loss and sorrow these people must have felt at the loss of their children," he said.