Infrasonic weapons just mentioned on Fox in connection with sonic disturbances causing sickness to US diplomats in Cuba and China.
Beat me to it anon (see post below yours). Think Infrasound needs some digging. Will try to do a bit myself but don't get much uniterrupted time so difficult for me to do a dedicated dig.
They're been reported longer than that. But now it appears thyey are being used. Anyway, it's INFRASOUND that interests me because of its devasting effects.
http://www.spannered.org/features/806/
"In the early 1970's, acoustic engineer Vladimir Gavreau was experimenting with infrasound weaponry. Now the stuff of infrasound legend, Gavreau was responsible for the construction of a giant 6ft whistle, powered by compressed air, which reputedly scrambled the inner organs of it's unfortunate operator (a phenomenon known as 'cavitation', where the internal physiology was fatally resonated). Distraught, Gavreau ceased his experiments, but left behind plans and models for highly sophisticated, directional sound cannons, which were apparently seized by the French authorities."
https://www.youtube.com/watch?v=epYQZ03pNK4&feature=youtu.be
3.05 mins
"I was taught how to bring down the twin towers with infrasound"
Dean Warwick
(Apparently 187'd shortly after interview)
https://www.youtube.com/watch?v=epYQZ03pNK4&feature=youtu.be
Twin towers brought down by infrasound