There isn't a clear motive yet, but it could be very well political as many of the victims were from Cuba's US embassy. It was recently reported that interesting sonic attacks are afflicting people in Cuba, including americans. The attacks, which haven't been exactly defined, are causing symptoms including headaches, nausea and other possibly-permanent traumatic brain ailments. Investigators have called this unprecedented and the US government is still developing a response to this cryptic phenomenon.
Search
Tuhin Chakraborty
Sep 2, 2017
Cuban Sonic Attacks
Cuban Sonic Attacks
It's interesting how this hasn't been covered too much by US news outlets, but the sources that have covered it say that the attacks are focused on the US embassy. "It comes as the union representing diplomatic staff says some victims suffered mild brain injuries and permanent hearing loss," BBC reports.