Authorities are investigating who is responsible for mailing what turned out to be harmless white powder to two Jewish organizations in Boulder County.
First, employees at the Jewish Community Center found white powder inside a letter with a threatening message Mondaymorning. Minutes after officials announced the powder didn't pose a danger, police responded to Congregation Har HaShem, a synagogue about five miles away, where a letter with white powder was also found.
Police spokeswoman Kim Kobel said workers were opening the mail outside after hearing about the first letter. Field test found that powder was also harmless. It wasn't immediately clear if that letter had a threatening message.
The investigation comes in the middle of Passover, the weeklong Jewish commemoration of the deliverance of the ancient Hebrews from Egypt.