http://www.nbcnewyork.com/news/local/Arrest-NYPD-Plot-Explosive-Blow-Up-Park-Arch-Greenwich-Village-186339271.html
"A man accused of keeping bomb-making materials in his Greenwich Village apartment told acquaintances late last year that he planned to blow up the Washington Square Park arch, police said Thursday.
The acquaintances have also informed police that in another encounter with Aaron Greene, they saw him sprinkle white powder on the sidewalk inside the park and ignite it, said Paul Browne, chief spokesman for the NYPD."
NYPD: Greenwich Village Man Planned to "Blow Up" Washington Square Park Arch