Police in this video say they don't give off any heat signature which is unusual for drone technology.
These are the points what I've gotten so far from following this story:
The drones are about car sized, which is bigger than commercial drones available for sale. I'm no drone expert, but I think only military/rescue drones are this size.
Despite their size, they are very quiet. Quieter than any drone that we know of.
They cannot be detected by infrared.
Their radio frequency cannot be intercepted, which could mean they are manned/programmed for set routes/or just have very sophisticated anti-jamming tech.
They evade detection from other drones and helicopters.
They can loiter for hours longer than conventional drones.
They are showing up in large numbers and apparently in other states and countries as well.
So somebody developed very high tech drones and are for some reason, deploying them in large numbers, without telling local governments, while not being all that secretive about it, to conduct...surveillance or something? WTF is going on?
If these are aliens, I would think the tech would be even more advanced, but this tech seems only about a decade or so more advanced than what we have. I could buy that this is some secret tech the US military is working on, but it doesn't make sense how the government is reacting. No communication between agencies, people in office, making a fool out of police agencies, etc.