By Natasha Brown

PHILADELPHIA (CBS) — “December 2, I was walking down the aisle and a rock came through the window,” said Malcolm Adler. He barely escaped the act of vandalism, unscathed.

Fast forward to Friday evening, January 6, just before services at Temple Menorah Keneseth Chai. This time, six windows were shattered by rocks.

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In both cases, the vandals struck around 7:30 p.m., just before services were to get underway. Adler is the president of the synagogue and he believes these were hate crimes.

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“We believe it was a hate crime. Both happened before services,” Adler said. He adds that the Anti-Defamation League is involved and also believes these were hate crimes.

Police continue to investigate to try to determine a motive.

The vandalism at the Tacony synagogue comes on the heels of bomb threats called in to Jewish Community Centers around the country on Monday. A Wilmington center was among those targeted.

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Adler explained that a security system and cameras will be installed at the Temple. He added that an anonymous donor in Florida has offered a $10,000 reward for information that leads to an arrest.