Bank of England Buys Bonds in Bid to Stop Spread of Crisis

LONDON—The Bank of England launched an emergency intervention to restore order in bond markets after a government tax-cut plan sent borrowing costs soaring and triggered a meltdown in complex financial instruments held by pension funds.

The BOE said Wednesday it would buy long-dated U.K. government bonds “on whatever scale is necessary” to calm markets and prevent the financial contagion from causing wider economic damage.