[GorillaMa]

Are the tones at the beginning of the audio phone key tones? It sounds like a number is being dialed.
After the phone tones, explosions. Perhaps this is hinting remote detonation by cell phone?

[KylaStarr]

>>Are the tones at the beginning of the audio phone key tones?<<

The tones sounded different than phone tones to me, more like an old tv audio test pattern sound, for want of a better description.

I just don’t know for sure.