The New England Holocaust Memorial in Boston was vandalized on Monday, for the second time in two months.

According to the Boston Herald, police arrested a suspect in the vandalism. They said the suspected smashed a glass panel on the memorial.

The memorial had previously been vandalized in June by a large rock that was hurled at it.

A local man, James Issac, 21, was arrested shortly after the discovery of the vandalism. He has since pleaded not guilty to two counts of willful and malicious destruction of personal property. His attorney said he suffers from mental health issues.

The memorial was rededicated just last month after the previous vandalism.

The six glass towers are lit internally and etched with millions of numbers that represent tattoos on the arms of many Jews sent to Nazi death camps.