Pink White House greets visitors on Thursday

Pink White House: President Barack Obama announced via Twitter earlier in the day that the building will be bathed in pink light Thursday, for breast cancer awareness.

The White House became the "Pink House" Thursday night for breast cancer awareness.

President Barack Obama announced via Twitter earlier in the day that the building will be bathed in pink light Thursday, just for one night.

Obama signed a proclamation at the beginning of the month designating October as National Breast Cancer Awareness Month. Last October, the Obamas hung a large pink ribbon on the Pennsylvania Avenue side of the White House.

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The American Cancer Society says there are roughly 40,000 breast cancer deaths each year in the U.S.

The main entrance to Vice President Joe Biden's official residence at the U.S. Naval Observatory also was to be lit in pink Thursday night.