Federal authorities have charged a former Norwich woman, who was arrested in 2009 for robbing six banks in six days, for robbing three more banks while she was on parole .

Heather Brown, 49, is facing charges related to three bank robberies in February, two in Waterbury and another in Bristol, Brown has been in custody since her arrest on Feb. 9.

In 2010, Brown was sentenced to 16 years in prison and four years of parole for committing bank robberies the previous year across three states. Four occurred at banks in Montville, Middletown, East Hartford and Windsor. The others were in Westerly, R.I., and Springfield, Mass. She was previously convicted of robbing a Groton bank in 2006.

The FBI on Thursday announced that a federal grand jury in New Haven returned an indictment with charges related to the three robberies. Brown, with a most recent address in New Haven, faces up to 20 years in prison for each of the robberies.