I ran across this article over on the Daily Mail Online. I wasn't familiar with Nick Pope or his work with the Ministry of Defense over in the U.K. but I found an audio interview with him here.

A few unnerving quotes from the artcile:

"If you believe these things are extra terrestrial craft then you cannot rule out that what is happening is some kind of covert reconnaissance."

"The consequences of getting this one wrong could be huge," he said."

"And while Mr Pope says that there is no evidence of hostile intent, he insists it cannot be ruled out. "

"There has got to be the potential for that and one is left with the uneasy feeling that if it turned out to be so, there is very little we could do about it," he said. "