London's Heathrow airport is closed after a major fire at an electrical substation caused a power outage.

120 flights were in the air and had to be turned around or diverted.

Heathrow is Europe's busiest airport. 

UK Correspondent Gavin Grey talks to Ryan Bridge about the shutdown, why former Scottish leader Nicola Sturgeon's no longer under investigation, and Finland's ranking as the world's happiest country.