[Periscopes and shaky youtube videos come in hot from a subway station late in the evening, just after the commuter rush. There were still good-sized crowds gathered on the platform when everything with with a screen in the vicinity flashed bright blue and started screeching at top volume. Every cell phone, every screen displaying track times, every tablet, every laptop. Any and all electronics were unresponsive while the hostile takeover was happening, including the station's CCTV cameras, meaning that there are only eyewitness accounts to testify to this terrifying disturbance.
When it ended, the power in the station went out. What videos there are show crowds of people running up the stairs and back onto the street, panicked under the scarlet glow of emergency lighting and the sound of sirens.
A number of people were injured in the stampede, but there were no deaths on the platform. The same goes for the trains that were near the station, which suddenly increased in speed for roughly the fifteen second period that the electronic disturbance was marked. There were thankfully no collisions, but some people were thrown when the cars jerked forward, and some fell during sudden stop a few moments later, as miles of track around the station all shut down at once.
The stalled subway cars led to train delays of many hours, well into the evening. As of early the following morning, authorities still have no explanation to offer. The most popular answer from conservative pundits? An act of mutant terrorism. The police insist they are still investigating, and ask the public not to rush to judgement, or to hasty action. They are collecting the devices of those who were in the station, but there doesn't seem to be any trace left behind by whatever caused this.
The sound was loud enough that it could be heard on the street. A few people, out of range of the disturbance, managed to record snatches. What little there is to decipher generally sounds like a loud burst of feedback. A few audio analysts swear they've found, in the layers of sound, a human scream.]