LONDON — The scale of the sexual abuse scandal at the BBC widened significantly Thursday as police reported that the number of people accusing one of Britain’s best-known television hosts of misconduct had risen to about 300 from 200, and said other people may have acted with him.

The police account also seemed to reinforce British news reports that the inquiries into accusations of sexual abuse against the host, Jimmy Savile, were spreading to broader questions about possible misconduct in other parts of the BBC and to suggestions of networks of abuse at hospitals associated with Savile’s ostensibly philanthropic works.