Tree Fell on Neighbors House

We had a tree that was approximately 60 foot high that snapped and fell onto our neighbors roof and did extensive damage during a noreaster. The neighbor says he informed us the tree was struck by lightening several months earlier and therefore we were negligent. The tree did not appear dead and when it fell we could see a section of it was hollow. This neighbor is extremely angry and has sent us a letter requesting we pay him his deductible since we were negligent. We had no idea the tree was damaged or would have had it cut down because if the wind had been blowing the other direction it would have destroyed part of our home. We just in 2005 had 3 trees cut down as we believed them to be damaged. I don't want to give him any money as he has implied that we will be admitting we were negligent. I don't know how to respond to this neighbor.

Unless it was very clear that the tree was ready to fall then you normally are not liable...you apparently thought it was okay as it could have harmed your own home if it fell...