When we consider all the selective memory on LIBOR at the moment, its always fun to go back and look at what was topical on this blog back then. 

I found this:

LIBOR and why it matters | risk that any bank could face a run on its deposits from May 8th, 2008

It was a concern because the hot topic was the high rates of LIBOR and the resultant high interest payments but large banks, and this 5 months before the Lehmans moment.

No evidence here of manipulation, but there is circumstantial evidence that the topic was under review by bankers and central banks.