Twenty-four gravestones at the Woodbrook Cemetery were knocked over by vandals over the weekend.
Police responded to the cemetery Saturday morning after a cemetery employee noticed the gravestones were knocked over in the main section of the cemetery that leads from the Salem Street gate to the Kendall Square gate.
Police believe that more than one person was involved because some of the stones that were damaged would have needed at least two people to push them over.
Some of the older stones were cracked in half.
Many of the stones will be repaired and placed back the plots, but a cemetery official said it will be “very costly.”
Woburn Police detectives are investigating the vandalism.