The package exploded at Capital Commercial Services, an insurance mediation company that represents such clients as the British Broadcasting Corp., the Criminal Records Bureau, the Department of Trade and Industry and the Department of Work and Pensions.
Police said the injured woman suffered minor injuries and was hospitalized.
The office was near Scotland Yard and several other government offices but police said the target was a business, reports AP.
Capita was formed in 1984 and has more than 26,000 staff in the United Kingdom, the Channel Islands, Ireland and India.
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