Nigel Farage says Ukip was becoming "increasingly alarmed" by MEP Amjad Bashir's behaviour in the months leading up to his defection to the Conservatives.
Speaking on BBC's The Andrew Marr Show, the Ukip leader said there was "quite strong documentary evidence" relating to what the party calls "unanswered questions" over employment practices at his business.
He also accused the MEP of "continuing associations with political extremists from Pakistan despite us saying please, please keep away", and said he was surprised that the Conservatives had accepted him
Bashir has denied any wrongdoing in relation to the allegations, and says Ukip's claims are a "desperate attempt" to smear him.
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