In the wake of Sunday’s fatal shootings at a Jewish community center and retirement home near Kansas City, a letter entitled “Security Protocol Review” went out Friday to Young Israel Orthodox communities in the United States and Canada, outlining security precautions for the Sabbath and Passover holidays.

The email, sent by Young Israel’s Assistant Director of Synagogue Services Ari Matityahu, urged heightened awareness, including taking note of illegally-parked cars, suspicious packages, and individuals loitering around Jewish sites or showing unusual interest in “entry points, peak days and hours of operation, security personnel, surveillance assets (including cameras), and access controls such as alarms, barriers, doors, gates, or locks.”

Individuals with clothing not appropriate for the season were also to be regarded with suspicion.

Community members were urged not to walk home from services alone, or let strangers into community buildings.

Community leaders were asked to have their facilities monitored by trained personnel who would be visible near security checkpoints “to deter unwanted activity,” as well as “secure trash containers so bombs can’t be hidden in them.”

Finally, they were told to “encourage employees, congregants and visitors to report anything that appears to be odd or suspicious.”

In addition, the letter encouraged communities and synagogues to communicate regularly with local law enforcement and rescue services.

According to Matityahu, the procedures outlined in the email were discussed in a recent phone call between representatives of Jewish Federations of North America, the Conference of Presidents of Major Jewish Organizations, Secure Community Network (SCN), the FBI, and Department of Homeland Security.