Questions about the underwater lights “UFOs”

I’ve notices a few underwater bright lights “UFOS”

One that has a bright light underwater that illuminates a weirdly moving figure. This one is claimed to be debunked as a diver.

There was another one today on a research ship.

It seems to me these could be divers, hoaxes by the posters just throwing in LEDs and taking photos, or better hoaxes where someone else is sinking lights underwater and letting them be discovered later.

It wouldn’t be hard or expensive to sink a battery and some bright LEDs, maybe on a timer. Inthink you would just need a waterproof container. These don’t seem to be coming from thousands of feet deep so it’s probably not too much pressure etc making it hard to do.

Is thete some way to determine what’s going on?