YEREVAN, MAY 10, ARMENPRESS. The Department of Homeland Security will release “harmless particle materials” in the city’s subway system, reports NY Daily News.

The “non-toxic, safe gas material” will be released at subway stations in Manhattan, Brooklyn, and Queens in order to understand where hazardous material would travel in the event of a biological terrorist attack

“This is important information to help local authorities to enhance their emergency preparedness,” DHS Program Manager Dr. Donald Bansleben said.

Officials said there is currently no credible threat against either New York City or the subway system.