Police say a white powder was discovered in a parcel inside the mail room for the New York building that houses the office for Manhattan District Attorney Alvin Bragg.  SEE MORE: NY grand jury reportedly won't meet about Trump this weekThe grand jury typically meets for various cases on Mondays, Wednesdays and Thursdays.  President Trump has announced his intention to run for president in 2024 and has various campaign stops scheduled in the weeks ahead including one in Waco, Texas