Criminal accusations were flying at Wells Fargo Chairman and CEO John Stumpf at a congressional hearing Thursday at which he admitted some retail banking workers stole money from customers in a phony account scam.

As Democratic members of the House Financial Services Committee claimed Stumpf and his executive team could be guilty of crimes from fraud to racketeering to identity theft, Republican Committee Chair Jeb Hensarling opened the hearing by saying:

“Fraud is fraud and theft is theft. All culpable individuals must be held accountable.”

The lead Democrat on the committee, Maxine Waters, said she will introduce legislation to break up Wells Fargo and possibly other big banks.

“Wells Fargo is too big to manage,” she said.

Stumpf seemed unfazed by the accusations that criminal activities by him and other Wells Fargo leaders led to workers creating over 2 million phony bank accounts and credit cards.

The company’s chief denied the scam represents the bank’s corporate culture.

“This is a holding company that made some mistakes. Wells Fargo is a great corporate citizen,” Stumpf said.

Several congressmen said Congress needs to investigate whether cross-selling scams are widespread in banking.

While Stumpf said he first learned about allegations of improper sales practices pressure in 2013, New York Rep. Carolyn Maloney said there is evidence in a Montana lawsuit that six employees were fired for failing to participate in the scam in 2007.