OCEAN COUNTY, N.J. (CBS) — A mystery washes ashore on a New Jersey beach. A skull showed up on Monday on the sand at Island Beach State Park in Ocean County.

The New Jersey Department of Environmental Protection shared the pictures on Twitter.

READ MORE: Philadelphia Mom Amber Nichols, 2-Month-Old Daughter Sophia Watson Located

We have confirmed that this is the ventral (lower) jaw and skull of a Minke whale. https://t.co/lIISxVAzYW

— New Jersey Department of Environmental