On the ITV coverage of the Belgium GP Max Mosely stated he'd received a telephone call after the Hungarian GP from Ron Dennis stating that Alonso had threatened to inform the FIA about more evidence on the Ferrari documents.(i.e the emails)
From the formal FIA hearing transcript...
"Referring to a conversation on the Sunday morning at the Hungarian GP, Dennis said that Alonso was "extremely upset with what had taken place the previous day, but nowhere nearly as upset as I was. He said things that he subsequently and fully retracted. Within the passage of material, he made a specific reference to e-mails from a McLaren engineer.
When he made this statement, I said, Stop. I went out, brought Mr Whitmarsh him in, and Fernando said everything again, in front of his manager. When he had finished, I turned to Martin Whitmarsh, asking what we should do with this particular part of the conversation. Martin said we should find Max. After Martin and Fernando left, that is exactly what he did. I recounted the entire conversation to Max. I was upset and angry, but mainly upset. Max calmed me down. He said that I should do nothing. I started to calm down. Then, prior to the race, Fernandos manager came and said that he had lost his temper and completely retracted everything he said. When I phoned Max, Max was understanding and said things to me that are irrelevant here, though I would be more than comfortable sharing them. He was completely understanding and said that, on the basis of what I told him, if he felt there was any real validity in what Fernando had said, he would contact me prior to taking any action."
Dennis went on to say that after the race Alonso "apologised for the outburst and I put it down to the heat of the moment, in which he was angry. That is how I took it. Other than following up with Martin, the matter ended there, until 26 days later, when the drivers received a letter. What took place between those times, I do not know. I do not know what circumstances brought that into the public domain."
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So Alonso made these "threats" in front of Ron Dennis, his own manager, and Martin Whitmarsh, McLaren CEO. He was also present when it was agreed to phone the FIA and tell them about the information, and he left happy in this knowledge. He later apologised to Ron Dennis for his outburst.
Those Spanish clearly have a strange idea of blackmail...