BOULDER, Colo. (CBS4) – A large-scale investigation is underway in Boulder after a threatening letter was sent to a Jewish center with a harmless white powder inside and two suspicious packages were found nearby. Another Jewish organization also received a letter with harmless white powder in South Boulder.

The events started when employees at the Jewish Community Center, located on the 3800 block of Kalmia Avenue, opened the envelope at 8:30 a.m. The letter said “You have enemies.”

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(credit: CBS)

(credit: CBS)

There were about a dozen preschool children in the building at the time, along with staff.

“There might have been 10 or a dozen children at the school, plus staff. So our first priority was to (evacuate) them to a safe location,” said Boulder Sheriff’s spokesman Cmdr. Jeff Hendry.

(credit: CBS)

(credit: CBS)

The Boulder County Health Department and a hazmat team responded to the incident, and an office where the letter was opened was isolated and the two employees kept safe. Everyone else was evacuated.

Those two employees were then medically treated by an ambulance crew.

(credit: CBS)

(credit: CBS)

“They are in great shape. A hazmat crew just got done with their work. They came from Boulder Fire Department and Boulder Rural Fire departments. They suited up, went into the building, brought the material out, tested it and it has come back as a benign substance,” Hendry said.

(credit: CBS)

(credit: CBS)

Sheriff’s officials said that while they were searching the area two packages were found and they were called suspicious. A bomb squad was called in to investigate.

“We did a secondary search of the area and found a couple of packages that were deemed suspicious,” Hendry said.

It’s not clear what was in the packages.

(credit: CBS)

(credit: CBS)

The threatening letter had a local return address authorities said officers were sent to that location to check it out.

“The letter itself was addressed to the community center and there was a return address on it,” Hendry said.

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The sheriff’s office has declined to give more information about the return address or if they have a suspect in their investigation. The FBI and a postal inspector are assisting police with their investigation.

The Congregation Har HaShem in South Boulder also received a letter with white powder on Monday just before noon.

“When they heard about the package that was received at the JCC earlier this morning they decided to look through the mail outside, and that’s when they found the suspicious package,” Rabbi Mark Glickman with Congregation Har HaShem told CBS4.

That powder was also found to be harmless.

“We feel very fortunate that our employees are safe,” Glickman said.

Additional Resources

The Boulder Jewish Community Center shared a notice they released to their community with CBS4:

Dear Boulder JCC Community,
At 8:30 this morning, a JCC staff member found an envelope containing white powder. We immediately evacuated the building and contacted the local Sheriff’s office. Both the Sheriff’s Office and Boulder Rural Fire responded immediately. They have secured the building and are going through the necessary protocol to ensure everyone’s safety. The Sheriff’s Office is investigating the incident and will notify us with any new information.

When events like these arise, the Board and Staff of the Boulder JCC take them very seriously. We place the safety and well-being of our community as our highest priority, and therefore wanted to share this information with you. We will continue to maintain a high level of safety and security and will keep you informed as we receive additional information.

Additional Information From The Boulder Police Department

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Anyone with information about the incident at Congregation Har HaShem is asked to call Boulder police at 303-441-3333. Those who have information but wish to remain anonymous may contact the Northern Colorado Crime Stoppers at 1-800-222-TIPS (8477) or 1-800-444-3776. Tips can also be submitted through the Crime Stoppers website at http://www.crimeshurt.com. Those submitting tips through Crime Stoppers that lead to the arrest and filing of charges on a suspect(s) may be eligible for a cash reward of up to $1,000 from Crime Stoppers.