The National Park Service is investigating an illegal excavation at Petersburg National Battlefield/NPS

While Americans this weekend honor those who gave their lives in defense of the country, the National Park Service is investigating looting that took place at a Civil War battlefield this week. The initial assessment at Petersburg National Battlefield in Virginia identified a large number of excavations in the park. Officials believe the thieves were looking for relics on a field where more than 1,000 Union and Confederate soldiers died fighting during the Siege of Petersburg.

“This is an affront to the memory of people who fought and died on this field, and it is destruction and theft of history from the American people,” Petersburg National Battlefield Superintendent Lewis Rogers said in a release. “This kind of aberrant behavior is always disgusting, but it is particularly egregious as Memorial Day weekend arrives, a time when we honor the memories of our friends and family.”

The affected area of the battlefield is an active crime scene, Mr. Rogers said. The remainder of the 2,700-acre park is open to visitors. Petersburg became the setting for the longest siege in American history when Gen. Ulysses S. Grant failed to capture Richmond, Virginia, in the spring of 1864. Grant settled in to subdue the Confederacy by surrounding Petersburg and cutting off Gen. Robert E. Lee’s supply lines into Petersburg and Richmond. On April 2, 1865, nine-and-one-half months after the siege began, Lee evacuated Petersburg.

Park staff discovered the excavated pits earlier in the week.

“Archaeological resources are a window to our nation’s history,” Mr. Rogers said. “Historians are still writing history based on the archaeological clues left by those who have preceded us. Removing these artifacts erase any chance for us to learn from our nation’s greatest tragedy.”

Since the park is nestled in an urban setting, Mr. Rogers said, “Someone may have seen something we need to know. The public can help by calling in any tips or other information.”

Anyone with information can call (888) 653-0009 toll-free and leave a message.

The looting at Petersburg National Battlefield is a federal crime covered by the Archaeological Resources Protection Act of 1979. Upon conviction, violators can be fined up to $20,000 or imprisoned for two years, or both.