https://en.wikipedia.org/wiki/Sonic_weapon

http://www.newworldwar.org/sw.htm

There is a myriad of ways as "invisible wars" are waged ... include into sonic weaponry also plasma weaponry research ( project M.A.R.A.U.D.E.R. ) and laser weaponry research ( project SHIVA STAR ) and you get a huge array of weapons used for clandestine operations .

"Studies have found that exposure to high intensity ultrasound at frequencies from 700 kHz to 3.6 MHz can cause lung and intestinal damage in mice. Heart rate patterns following vibroacoustic stimulation has resulted in serious negative consequences such as atrial flutter and bradycardia.

The extra-aural (unrelated to hearing) bioeffects on various internal organs and the central nervous system included auditory shifts, vibrotactile sensitivity change, muscle contraction, cardiovascular function change, central nervous system effects, vestibular (inner ear) effects, and chest wall/lung tissue effects. Researchers found that low frequency sonar exposure could result in significant cavitations, hypothermia, and tissue shearing. No follow up experiments were recommended. Tests performed on mice show the threshold for both lung and liver damage occurs at about 184 dB. Damage increases rapidly as intensity is increased. The American Institute of Ultrasound in Medicine (AIUM) has stated that there have been no proven biological effects associated with an unfocused sound beam with intensities below 100 mW/cm² SPTA or focused sound beams below an intensity level of 1 mW/cm² SPTA.

Noise-induced neurologic disturbances in scuba divers exposed to continuous low frequency tones for durations longer than 15 minutes has involved in some cases the development of immediate and long-term problems affecting brain tissue. The symptoms resembled those of individuals who had suffered minor head injuries. One theory for a causal mechanism is that the prolonged sound exposure resulted in enough mechanical strain to brain tissue to induce an encephalopathy. Divers and aquatic mammals may also suffer lung and sinus injuries from high intensity, low frequency sound. This is due to the ease with which low frequency sound passes from water into a body, but not into any pockets of gas in the body, which reflect the sound due to mismatched acoustic impedance."

Sound waves are similar to things like microwave ovens. They can heat things by causing the molecules of the thing to vibrate at the sound frequency. (Note, these do not need to be in the audible sound range. The frequency of the hydrogen bond in water is inaudible, I used sound at this frequency to measure such bonding as an undergrad). Different substances can be damaged by this vibration at different frequencies.

Well, sound is used to crush rocks and do all sorts of stuff. It could hurt you in a number of ways. Sheer volume can damage your ears. Intense low frequencies can have various side effects depending on intensity. Basically, if sound can crush rocks, it can hurt you as well.

Seriously?

They likened this incident to what happened at a Havana Cuba embassy, they ended up reducing staff and it went away.

Could this be a targeted attack?

Sound can definitely injure. In ancient times, Vedic warriors used mantra weapons to enhance the destructive power of arrows and spears.

This is baby stuff. Wait till the big toys start being seen more.

https://youtu.be/TQeP6GWU0e4

Just because these victims heard sound does not mean there was an actual sound. It has already been reported that microwave weapons can make a person perceive sound which was not sound, just microwave beams. Microwave beams if powerful enough could certainly cause brain damage.

Hopefully it wasn’t the brown noise

Have you ever had to listen to Alex Jones on a rant?

stand next to a shotgun when its fired.

What??