Donald Trump's wall: How tech guards the US-Mexico border February 09, 2019 at 04:36PMhttps://https://bbc.in/2BsTvPL Camera-laden towers and underground sensors plug the gaps in the existing US-Mexico border fence.

Camera-laden towers and underground sensors plug the gaps in the existing US-Mexico border fence.

from BBC News - World https://bbc.in/2SC1TGG