Sens. Elizabeth Warren (D-MA) and Chris Van Hollen (D-MD) want to know whether any Mar-a-Lago members had advanced knowledge that the Trump administration would kill a top Iranian general — and whether they used that knowledge to game the stock market.

The American killing of Iranian Gen. Qassem Soleimani by a drone strike outside Baghdad International Airport rocked the region and has led to Trump administration dissembling over the reason for the strike. The killing took members of Congress and American allies overseas by surprise, but, according to the Daily Beast’s reporting on the day of the attack, some people had hints it was coming: members of the President’s pricey private South Florida club, Mar-a-Lago.

Unnamed sources who’d been at the club in the days leading up to the strike told the Daily Beast that Trump told people at the club that there would be a “big” response to Iran’s recent actions in the region “soon.” Trump reportedly mentioned talking to his military advisers about impending action against Iran.

For Warren and Van Hollen, that rang insider trading alarm bells.

“Individuals who were guests at President Trump’s resort may have obtained confidential market-moving information and had the opportunity to trade defense industry stocks or commodities or make other trades based on this information,” they wrote to the chairmen of the Securities and Exchange Commission and Commodities Futures Trading Commission.

In the hours after the attack, the senators pointed out, stock prices for military contractors Northrop Grumman, Lockheed Martin and Raytheon increased over 5%, 3.6% and 1.5%, respectively. Crude oil prices also jumped more than 4%.

Warren and Van Hollen asked the SEC and CFTC to find out who Trump spoke to about the attack in the days prior, what specific knowledge those people had, and whether they used the information to illegally invest in the stock market. The senators also asked for a staff briefing on the the matter by Feb. 13.

Read the senators’ letter below: