Channel 4 has said one of the production team has written the message to the housemates, but would neither confirm or deny whether Big Brother was telling the truth.
Another Channel 4 source said: "There is a mole in the 'Big Brother' house this year."
Although the finger has been pointed at Makosi, who has twice been a 'Big Brother' informant as the 13th unlucky housemate and smuggling in two extra housemates, it is unlikely to be her as a spokeswoman at Channel 4 said today "As far as we're concerned it is not Makosi."
Kemal is the most obvious choice because he is a drama student and would find it easy to act up in front of the cameras.
A story is expected to be released to one of the national tabloids this weekend.
Meanwhile in the house, Craig has already been quizzing Big Brother about what the mole story can mean, saying that he trusts only Anthony and Science not to be the mole. "That message was a bit weird, the one about the mole," he said in the diary room.
Vanessa also had a theory about who the mole might be -- although she had to be told what a mole was before she coined her theory.
Makosi told Vanessa, who is favourite to leave tonight: "A mole is in the context of Big Brother, is not a contestant, they are somebody working with Big Brother against housemates."
Vanessa responded by telling Makosi: "It's so you. You are so the mole."
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