One of Justice Amy Coney Barrett’s sisters was targeted with a hoax bomb threat last weekend, police in Charleston, S.C., revealed on Wednesday.

On Saturday, an employee of the Charleston County Sheriff’s Department received a politically charged email concerning Amanda Coney Williams that claimed there was a “potential explosive device” in her mailbox. It was seemingly written by an anti-Israel advocate.

“Using a 1×8-inch threaded galvanized pipe, end caps, a kitchen timer, some wires, metal clips and homemade black powder, I’ve constructed a pipe bomb which I recently placed in Amy Coney Barrett’s sister’s mailbox at her home,” the email stated. “The device’s detonation will be triggered as soon as the mailbox is next opened. Free Palestine!”

The employee didn’t read the email until Monday morning. That’s when the police arrived at Williams’s house. The bomb threat turned out to be a false alarm once authorities opened the mailbox to inspect the alleged explosive, according to news reports.

Williams’s husband, David, told investigators that an unknown person attempted making pizza deliveries to several households belonging to relatives of Barrett last weekend around the time that the email was sent. It’s unclear if the two incidents are related. The investigation remains active, police said.

Several federal judges in the Washington, D.C., metro area have reported receiving anonymous pizza deliveries to their homes, Reuters reported. Police interpreted the unusual deliveries as a form of intimidation.

The threat against Barrett’s sister comes as concerns about judges’ physical safety have become increasingly common in recent years. The issue of politically motivated violence against judges and their relatives, which may be precipitated by doxxing, was raised in Chief Justice John Roberts’s latest year-end report.

Justice Barrett, whom President Donald Trump appointed in 2020, faced criticism from conservatives after she voted to reject the administration’s attempt to freeze $2 billion in foreign aid earlier this month. She sided with Roberts and the Supreme Court’s three liberal justices in the majority opinion, while the Court’s remaining four conservative jurists dissented.

Although Barrett faced pushback from Trump supporters, prominent legal conservatives rushed to her defense.

“She’s been in the vanguard of conservative jurisprudence on abortion, racial preferences, the administrative state, religious freedom, Trump immunity, guns and the Second Amendment,” Leonard Leo, board co-chairman of the Federalist Society, told CNN.

Leo described the Supreme Court’s disagreement in the dispute involving Trump’s presidential control over the U.S. Agency for International Development as a “procedural” one. “Those things happen quite often among conservative justices,” he said.

Notably, the conservative legal activist advised Trump on Supreme Court nominees during his first presidential term that led to the appointments of Justices Neil Gorsuch, Brett Kavanaugh, and Barrett. If those three weren’t selected, it’s highly unlikely Roe v. Wade would have been overturned by the Dobbs decision in 2022.