The US Department of Justice has opened an investigation into the collapse of Silicon Valley Bank (SVB).

SVB, a fintech-heavy California lender that was taken over by federal regulators last week after a rush from depositors to pull their money from the bank, is also facing civil lawsuits over complaints of fraud.

It’s not clear yet what DOJ investigators are focused on, but it could be related to massive sales of company shares by bank executives in the weeks before the bank collapsed.

Those sales generated millions of dollars.

The S.E.C. has also opened an investigation, which will be led by the commission’s office in San Francisco. Experts believe they will be looking at insider sales.

Some politicians are pressing for the bank executives to return any money they made from those stock sell-offs.