The concrete urn, a decorative replica of the original dated to the early 20th century, was pushed off the edge of the receiving vault at the tomb, where it fell and shattered. Nothing else was damaged, the Springfield State Journal-Register reported Wednesday.
The broken urn was discovered Jan. 2 by a cemetery employee who notified police. The property visited by generations of school children on field trips is guarded by surveillance cameras, but it is unknown if anything useful to police was captured, the Journal-Register reported.
Lincoln's tomb was built between 1869 and 1874 and is the final resting place of Abraham Lincoln, his wife Mary Todd, and three of the couple's four sons. The tomb has been the target of vandalism before, once in 1987 and again in 1997, at which point then-Governor Jim Edgar ordered 24-hour monitoring of the tomb.