The Securities and Exchange Commission is investigating the conduct of First Republic Bank executives before the government seizure and sale to JPMorgan Chase, Bloomberg News reported on Friday, citing people familiar with the matter.

The SEC is looking into whether any members of the then-executive team of First Republic improperly traded on inside information, according to the report.

JPMorgan declined to comment, while First Republic and the SEC did not immediately respond to Reuters’ requests for comment.

The development comes a day after Sen. Elizabeth Warren accused First Republic executives of “mismanagement” in a letter to its former CEO Micahel Roffler and raised questions on the failed lender’s risk management as well as pay and bonuses.

Regulators seized troubled First Republic Bank and JPMorgan agreed to buy majority of its assets earlier this week, marking the largest US bank failure since the 2008 financial crisis.