"Some top JPMorgan Chase executives and directors were alerted to risky practices by a team of London-based traders two years before that group's botched bets cost the bank more than $2 billion," The Wall Street Journal is reporting.

The Journal says it reached that conclusion after "interviews with more than a dozen current and former members of the bank's Chief Investment Office, the unit responsible for the losses."

And it adds that "last year, top CIO executives set a plan to roll back a separate set of large London trades — only to learn later that the plan hadn't been followed correctly."

Support for GBH is provided by:

This news comes one day before JPMorgan CEO Jamie Dimon is due before the Senate Banking Committee, which has scheduled a hearing on "A Breakdown in Risk Management: What Went Wrong at JPMorgan Chase?"

As we've previously reported, the banks losses on the bets were initially estimated at $2 billion — but have been growing.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.