That whole Brooklyn Bridge story seems fictional to me. No witnesses till months and years after?
http://www.csicop.org/si/9703/hopkins.html
No one was clamoring for information about radiation and syphilis. PROOF of UFO's couldn't last 5 years under wraps, not without human extermination. Let's hope that's not the case, if so, we have more to fear than just the aliens.
There have evidently been 100's killed to keep them quiet.
I think you have misread the evidence about the Brooklyn Bridge abduction. There's been tons of followup on it. Lots of things have checked out.