The former longtime treasurer and tax collector in a Delaware County township pleaded guilty Thursday to filing false income tax returns for five consecutive years, undervaluing her income by more than $400,000.

Rosezanna Czwalina, 69, was charged in April with five counts of tax fraud. Federal prosecutors said Thursday that Czwalina owes the government more than $100,000.

Czwalina served as the tax collector and treasurer in Ridley Township for 30 years before retiring in December. From 2014 to 2018, prosecutors say, she failed to report on her income tax returns the fees she was authorized to collect from duplicate tax bills and other services she provided the township.

» READ MORE: Former Ridley Township tax collector charged with filing false tax returns

There was some initial confusion during the proceedings Thursday in front of District Judge Paul S. Diamond when Czwalina said she didn’t remember the exact amount of money she failed to report each year.

A visibly irritated Diamond called for a brief recess to allow Czwalina and her attorney, Eugene Bonner, to review the evidence presented by prosecutors.

“The idea that you stole over $100,000 from the government by failing to pay more than $400,000 in taxes but you don’t remember the amounts simply won’t do,” Diamond said.

When the proceeding resumed, Czwalina entered her guilty plea, and the judge accepted it. When she is sentenced in September, Czwalina faces a maximum penalty of 15 years in federal prison and more than $1 million in fines.