The US Army Knows That Bigfoot Exists?!

There are some people who think the United States government knows Bigfoot exists. Many also think they know UFOs and such exists, myself included, but I'm not going to go into that right now.
Army Corps of Engineers says Bigfoot exists in Northwest US and Siberia
News article on Bigfoot' recognition by US Army
from Examiner.com
There's an article on Examiner.com titled "Bigfoot declared to exist in 1974.' It says that in that year the US Army officially recognized the creatures known as Bigfoot/Sasquatch to be living in the US and Russia.

The Washington Enviormental Atlas even included Bigfoot as a creature living in the state that year. The atlas said that the FBI had done testing on Bigfoot hair samples that did not come back as any human or known animal. The atlas desribed Bigfoots as being 8 to 10 feet tall, weihgning up to 1000 pounds and with feet up to 24 inches long.

The atlas stated that the FBI could not provide any info on the hair samples. Why? Were they told to cover up Bigfoot? Many people think the US government does cover up Bigfoot. What do you think? Do they, and if so, why?