Crooked financier Bernard Madoff has been sentenced to 150 years in prison for swindling investors out of billions of dollars. The 71-year-old American admitted masterminding a massive "Ponzi" pyramid scheme that duped thousands of investors. Madoff, who previously enjoyed a respected, high-profile Wall Street career, faces the prospect of spending the rest of his life behind bars. He pleaded guilty in a New York court in March to 11 charges of fraud, perjury and false reporting. The financier, a former chairman of the Nasdaq stock exchange, apologised for his actions, claiming the fraud began in the 1990s in response to the pain of recession. He told the court he was "deeply sorry and ashamed" about his crimes. He said he knew the fraud was "wrong" and "criminal" but added: "I believed it would end shortly and I would be able to extricate myself and my clients from the scheme." As time went on it proved "difficult" and then "impossible" to end, he said. Madoff and his wife Ruth lived a life of luxury, with homes in Manhattan, the Hamptons and Palm Beach, Florida. He was known for his charitable work and until his arrest in December he was seen as a champion of transparency and integrity. His investors included Madoff's friends and neighbours, as well as charities and banks such as HSBC and Abbey owner Santander. British businesswoman Nicola Horlick hit the headlines when it emerged she managed Bramdean Alternatives, which had 9 per cent of its funds invested with Madoff's scheme.