Millbury police are asking for the public’s help to identify four people seen building a swastika this week from cinder blocks on the high school’s athletic track.

Police released a grainy Millbury High School surveillance video Tuesday that shows the suspects walking toward a pile of blocks stacked next to a shed, then moving them, one by one, to create the shape of the anti-Semitic symbol.

“They initially pass by a pile of cement blocks, which are used to hold the tarps down on the baseball field. A short time later they return and two of the four subjects start selecting blocks and systematically place them down,” police said in a statement describing the video.


The incident took place around 12:29 a.m. Monday, police said.

Police said it appeared that one of the people in the video took a photo of the vandalism. The people then walked away from the cinder blocks and out of view of the camera, entered a vehicle, and left.

A runner discovered the swastika while exercising on the track around 5:20 a.m. Monday morning.

“We are taking this matter very seriously,” police said in a statement released Tuesday.

Anyone with information is asked to contact Millbury Police Lieutenant Donald Desorcy or Detective Kimberly Cadrin.

Steve Annear can be reached at steve.annear@globe.com. Follow him on Twitter @steveannear.