Nigeria is threatening legal action against the UK government unless it returns, with interest, £3m ($5m) that it says was stolen from its central bank. The money - a small fraction of the billions of dollars thought to have been plundered by Sani Abacha, the late African dictator - was seized in 1998 from a Nigerian businessman at Heathrow airport. The UK Treasury acquired the money after the customs service argued it was probably the proceeds of drug sales.