Eight Democratic senators led by Elizabeth Warren are asking the Department of Labor to investigate whether Wells Fargo was also violating labor laws, by punishing employees and forcing overtime hours, in its creation of phony bank and credit card accounts.

Regulators have recently said the company may have opened as many as 2 million such accounts under customers’ names without their authorization.

“The emerging portrait of the company's actual behavior suggests potential widespread exploitation of its own workforce in order to facilitate the widespread exploitation of its customer base,” the senators said in a letter to U.S. Secretary of Labor Thomas Perez.

That exploitation included reports from current and former Wells employees of threats of termination, mandated hours of unpaid overtime, harassment and other forms of retaliation for failing to make the aggressive sales quotas, the senators wrote, and could be violations of the Fair Labor Standards Act.

The activities barred by the law that facilitated the fraud could include the bank’s failing to pay overtime to bank tellers and associates who stayed late or came in on weekends to meet their sales quotas, or the bank’s misclassifying of salaried bank associates as overtime-exempt to avoid paying the overtime guaranteed, the letter said.

In addition to Warren of Massachusetts, the Democrats signing the letter were Sherrod Brown of Ohio; Jack Reed of Rhode Island; Kirsten Gillibrand of New York, Jeff Merkley of Oregon; Bernie Sanders of Vermont; Robert Menendez of New Jersey and Mazie Hirono of Hawaii.