Look at this YouTube videos showing very clearly the impressive and strange lights that were seen in Peru during the Earthquake two days ago:
Skip to 00:40 to see the amazing light.
Now look at this one:
This video was recorded by a team of reporters from a local news program. The place is Javier Prado Av. one of the main avenues in Lima, Peru. At the moment of the filming there's a major blackout in Lima.
In this third video, filmed during the quake, you'll see the earthlights if you skip till 00:48. The whole thing is very little known. The guy with the camera says "Wow! What's that?".
The explanation to the phenomenom seems to be Triboluminescence.
More links to this Earth lights phenomenom are here: