TACONY (WPVI) -- For the second time in as many months, vandals have damaged stained glass windows at a synagogue in the Tacony section of Philadelphia.It happened at Temple Menorah Keneseth Chai on Tyson Avenue.President Malcolm Adler recalls the first incident on December 2."I was walking down the aisle here to talk to the Cantor," President Malcom Adler said, "[when] the rock came through the window, the size of a baseball."Last Friday more rocks were thrown and a total of six windows were broken.The congregation started here in 1915 and the larger current building opened in 1951.Both rock throwing incidents occurred as Friday evening Sabbath services were to begin. Adler views the vandalism as crimes of hate."I know recently the anti-Semitism is happening with us," he said.More than a decade ago someone painted a swastika on the building, but recently there have been no other threats to go along with the rocks thrown."Nothing someone could look at and say 'you know what, maybe that's related to this.We don't know of anything related to this," Adler said.When the windows were replaced back in December, it cost $350 for a single pane of 16 inch by four foot glass.On Monday, Mark Allendorf was measuring for replacement panes. He lives in the area and is with a union that has offered to do the replacement for free."Labor for free, we will donate the glass. We will come by with a group of guys, and we will come in and fix it," he said. "We're just giving back to the community."The hope is to have the glass replaced this week.Meanwhile, there has been fundraising on social media for a security camera system in hopes of being a deterrent against future vandalism.