A red arrow points to Akayed Ullah, accused of triggering an explosion in the New York City subway system Monday. The image is from surveillance cameras in the commuter tunnel near Times Square; it’s part of the federal complaint against Ullah.

A red arrow points to Akayed Ullah, accused of triggering an explosion in the New York City subway system Monday. The image is from surveillance cameras in the commuter tunnel near Times Square; it's part of the federal complaint against Ullah.

A red arrow points to Akayed Ullah, accused of triggering an explosion in the New York City subway system Monday. The image is from surveillance cameras in the commuter tunnel near Times Square; it’s part of the federal complaint against Ullah.

A red arrow points to Akayed Ullah, accused of triggering an explosion in the New York City subway system Monday. The image is from surveillance cameras in the commuter tunnel near Times Square; it’s part of the federal complaint against Ullah.