Some Londoners may not be resting easy during the Olympics.
The British Ministry of Defense distributed these leaflets to a densely populated neighborhood in east London.
They notify residents of the possibility that surface-to-air missiles could be placed on a water tower in the neighborhood.
A ministry official says it's part of an air security plan for the Olympics, which also includes fast jets and helicopters to protect London air-space during the Games.
The 2012 Summer Olympics run from July 27th to August 12th.
Then the Paralympics are from August 20th to September 9th.