Lord McAlpine, who announced he was dropping defamation claims against Twitter users with less than 500 followers, said he wanted to draw the "unfortunate episode" to a close.
He has written to those tweeters and asked them to make a voluntary donation of £25 to the BBC's Children In Need as soon as possible.
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Rescue workers are at the site Sunday morning trying to cut open mangled coaches.
Despite chilly temperatures it will be a mostly dry day, and milder than yesterday.
The Sunday Times alleges a missile malfunctioned after launch during a routine test of the UK's nuclear deterrent last year.