LOWER MANHATTAN (PIX11) — Members of a Manhattan grand jury considering a possible indictment of former President Donald Trump have been asked to return Monday to court, where security remains high ahead of the momentous decision.

The case concerns hush money paid during Trump’s 2016 presidential campaign to adult film star Stormy Daniels, who alleged a prior sexual relationship with the Republican.

Trump had publicly claimed that he would be arrested on March 21, but that day — as well as the rest of last week — came and went without a grand jury vote on whether or not to recommend indictment.

The panel is set to reconvene Monday, under a cloud of threats against the office of Manhattan District Attorney Alvin Bragg. On Friday, a powdery substance was found in a delivery to the office’s mailroom, along with a letter threatening Bragg’s life. The substance was ultimately found not to be dangerous, according to a spokesperson for Bragg.

In making his incorrect announcement of his March 21 arrest, Trump called on his supporters to protest. Since, his social media posts have included a prediction of “potential death & destruction” should he be indicted, as well as a since-deleted photo of him holding a baseball bat next to another photo of Bragg, which even Trump’s lawyer, Joe Tacopina, described as “ill-advised.”

The NYPD, as well as state and federal law enforcement, have stepped up security in Lower Manhattan in preparation for possible unrest resulting from any indictment decision. Trump and his allies have claimed that the grand jury proceedings, which come amid his run for another term in the White House, are politically motivated on the part of Bragg, a Democrat.

Michael Cohen, a former longtime lawyer for the Trump Organization and a key witness in the proceedings, previously pleaded guilty in connection to hush money paid to Daniels and another woman making similar claims, model Karen McDougal. Cohen alleges that the payments were made at Trump’s direction.

Trump has denied wrongdoing and characterized Cohen as a liar.

This article includes reporting from the Associated Press.