COROLLA, N.C. (AP) — A foal born this year to a herd of wild Spanish mustangs that roams North Carolina’s Outer Banks has died unexpectedly, according to a group that manages the herd.

The foal named Charlie was born in late March and appeared to be healthy until his death, the Virginian-Pilot reported, citing the Corolla Wild Horse Fund.

The group said in a Facebook post that Charlie was seen on camera footage walking near his mom on Thursday afternoon. Minutes later he laid down, and he died within about 10 minutes.

“His parents and brother are fine and behaving normally, though of course were very distressed by his sudden loss,” the post said.

A necropsy was planned for Friday.

Charlie was the first foal born this spring to the group that lives along the northern beaches in Currituck County, the newspaper reported. Three more have been born since then.