An investigation is under way after more than 50 tombstones and memorials were vandalized at Brooklyn's historic Green-Wood Cemetery this week, with repairs estimated to cost more than $100,000. NY1's Arlene Borenstein filed the following report.

An 800-pound marble obelisk toppled over. Crosses, tombstones, some more than 100 years old, now overturned and broken at the historic Green-Wood Cemetery.

"It makes no sense whatsoever," said Ken Taylor, the vice president of operations for Green-Wood Cemetery. "It seems that they did this with a certain vengeance that I've never seen before."

Cemetery officials said some time after closing Monday night, one or more vandals climbed a fence near Fifth Avenue and 36th Street. A security guard was on patrol but it wasn’t until the sun came up that maintenance crews discovered all the damage. In total, 51 monuments were damaged or destroyed.

Jeff Richman is the cemetery's historian. He's helped identify Civil War veterans buried at Green-Wood. He said at least one soldier's tombstone was vandalized.

"Vandals here knocked the top of the monument off," Richman said. "It was put back up but now the granite is chipped."

In the path of destruction, the vandal or vandals targeted the tombstone of a five year old child, pushing over a statue of an angel that’s rested here for more than 100 years.

"I'm stunned that someone has to desecrate something that is precious," said Virginia Stevenson, who has generations of family members buried at Green-Wood. "What kind of people would do this? How can they do it? It's awful!"

Cemetery officials said they've given surveillance video to police but wouldn't say what it shows. They did say they've doubled their evening security patrols.

500,000 people, including actors and politicians, were laid to rest at the national landmark over the past 174 years. But with many of the families long gone, the cemetery is now asking for the public's help in making more than $100,000.

Anyone who would like to donate to help pay for the damage can visit green-wood.com.