British bank Barclays on Tuesday launched plans to raise £5.8 billion ($8.9 billion, 6.7 billion euros) via a shares sale to bolster capital levels, but revealed that first-half profits more than quadrupled. The lender, which was hit last year by the Libor rate-rigging crisis, said in a statement it would seek the capital boost in order to meet capital requirements laid down by the Bank of England.