As Prime Minister Theresa May promised, troops have been deployed to guard “key locations,” including the Palace of Westminster, several embassies and “other sensitive sites,” in London and other British cities, the Evening Standard reported. The mass deployment follows Monday’s attack at Manchester Arena, which killed 22 kids attending an Ariana Grande concert, as well as the 23-year old attacker. It was the worst terror attack in the U.K. since 2005.