Three possible mass shootings were thwarted in recent days. Ohio police arrested a white supremacist Saturday after he posted a video appearing to threaten a Jewish community center. Twenty-year-old James Patrick Reardon posted an Instagram video last month showing a man shooting a semiautomatic firearm as sirens blare and people scream. The accompanying caption reads, “Police identified the Youngstown Jewish Family Community shooter as local white nationalist Seamus O’Rearedon.” The Instagram post tags the location of the Jewish Community Center of Youngstown. The FBI raided his house Friday, seizing semiautomatic weapons, dozens of rounds of ammunition, a gas mask and bulletproof armor.

Meanwhile, Florida authorities arrested 25-year-old Tristan Scott Wix Friday after he sent text messages to an ex-girlfriend saying he wanted to commit a mass shooting. One of the messages said, “A school is a weak target.. id be more likely to open fire on a large crowd of people from over 3 miles away.. I’d wanna break a world record for longest confirmed kill ever.”

And in Connecticut, 22-year-old Brandon Wagshol was arrested and found in possession of a cache of weapons and ammunition after a Facebook post showed he may be planning a mass murder.

Gun control advocates rallied in cities nationwide this weekend to call for Congress to pass background checks on all gun sales and so-called red flag legislation, which allows family members to ask a judge to temporarily prevent someone from owning a firearm if they pose a risk of committing violence.