The woman, believed to be from Sierra Leone, was arrested on Friday after it was discovered that her passport was forged. She had been working in the Palace of Westminster for two months as a casual member of the catering team after being supplied by an external recruitment agency. It is believed that the agency had been responsible for performing checks on her background. Her status as a casual worker meant that she was required to be escorted at all times on the parliamentary estate. Parliamentary authorities did not respond to a request for a comment on the allegation that the woman was using someone else’s pass.