The attack purportedly involved multple attackers infiltrating from Canada, catching a PATH train and then timing the explosion in the under-river tunnel in an attempt to flood below-ground portions of the financial district. Story from Reuters here.
 NEW YORK (Reuters) – U.S. authorities thwarted a foreign-based plot to stage a suicide bombing of a rail tunnel in New York later this year and three suspects are being held abroad, one of them in Lebanon, U.S. officials said on Friday.Â
A Port Authority officer at the entrance to the Holland Tunnel in Jersey City, August 27, 2004. A plot to bomb the tunnel in an effort to flood the Wall Street financial district has been uncovered by the FBI, with a suspect arrested in Lebanon, New York’s Daily News reported on Friday. REUTERS/Chip East
Five of the suspects are still at large, and folks are still debating whether an explosion in Holland Tunnel would flood. Much of the infrastructure in Manhattan is below-ground, and there are coffer-dams & bulwarks in many areas that are below river level, so it’s plausible. It would take a physicist or hydraulic engineer however to measure the rises, forces req’d and potential siphon effects to determine for certain if the attack would cause flooding. All we know at this point is that Al Qaeda thinks it might, and they weren’t wrong on the structure of the Twin Towers. I wouldn’t write it off as “impossible” until I got a hydraulic engineering specialist involved.Â
A full comprehensive rundown can be found here. And Here.
Updated AP story with map here.