The Mercer Island Police Department’s Criminal Investigation unit is investigating a string of “felony level” malicious harassment/hate crimes that occurred on Mercer Island over the last week.

The most recent incident took place early Friday morning at the Northwest Yeshiva High School. The suspects, including at least three “older juvenile” boys, defaced the campus with swastikas and other anti-Semitic graffiti. A school surveillance camera caught the trio on tape at 1:45 a.m.

Similar graffiti was also reported at St. Monica Catholic Church. The building, as well as two cars, a truck and a van, were also spray-painted.

Police suspect that these two incidents may be related to a third graffiti report received on Sept. 14 from the Island Park Elementary School. Employees arrived to find graffiti that targeted “police as well as specific ethnic and religious groups,” according to officials investigating the crimes.

Mercer Island residents weren’t about to silently take the abuse. After learning of the graffiti at Yeshiva, Islander Rebecca Warriner organized a group of friends on Facebook.

“Tomorrow is Yom Kippur, so many of our Jewish neighbors will not be able to join us. And, quite frankly, I hate the idea of them needing to do so on one of the holiest days of their year. So, I feel it is even more important that our community rally and balance out the negativity of these actions,” she wrote.

Warriner encouraged her friends to join her for an hour on Friday morning at the intersection of Island Crest Way and S.E. 40th Street, and bring homemade signs or just stand in support if they were unable to make a poster.

Tana Senn, a Mercer Island mother of two, joined the group of about 30 people who came out to support the impromptu rally.

It was a great learning experience for her two children, 8 and 5 years old, who joined her, she said.

“I really wanted to let them know that they can stand up for things that are important,” she said. “You don’t just talk; you take action.”

The experience provided a good discussion point to talk about disrespectful behavior, and these types of threats shouldn’t discourage any family from continuing to practice their beliefs, said Senn, who practices Judaism.

Other parents with kids in tow joined the group, she said. After the rally, Senn received several e-mails from Jewish and non-Jewish friends who drove by the rally and supported her efforts to combat the negativity of the recent rash of anti-Semitic graffiti.

“That was the goal,” Senn said of others in the community becoming aware of the crimes and supporting their neighbors.

The Mercer Island Police Department is continuing to investigate these crimes and urges anyone with information to call the tip line at (206) 275-7955. More updates will be posted as they become available.