BERLIN — A German woman suspected of being the last surviving member of a neo-Nazi group accused of killing nine immigrants and a policewoman from 2000 to 2007 broke her long silence on Wednesday, admitting to a Munich court that she was “morally guilty” of failing to prevent crimes but denying any part in the murders.

The woman, Beate Zschäpe, 40, had refused to make any statement to the court since her trial opened in May 2013. Two years earlier, she had walked into a police station after two male associates were found dead in the wake of a failed bank robbery.

The case shook Germany because the killings of the immigrants and policewoman had gone unsolved for years and because the neo-Nazi group, the National Socialist Underground, had seemed to escape official attention for a long period. Ms. Zschäpe’s refusal to discuss her potential role had added to the interest in the trial.

On Wednesday, her lawyer read from a 53-page statement in which Ms. Zschäpe said she had gone underground with the two men in 1998. She denied, however, that she was a member of a far-right organization, and said she had not taken part in the killings of the immigrants and had not had any knowledge of the deeds. She also rejected having had a role in two bombings in Cologne, in January 2001 and June 2004, of which she is also accused.