Prediction market users have made — and profited from — big bets around the bombing of Iran by the U.S. and Israeli military.

On Polymarket, $529 million was traded on contracts tied to the timing of the attack, according to Bloomberg. An analysis by analytics firm Bubblemaps SA found that six newly-created accounts made a profit of $1 million by correctly betting that the U.S. would strike Iran by February 28 — behavior that could indicate insider trading.

The bets might merely reflect broader speculation about U.S. intentions in Iran, but Bubblemaps CEO Nicolas Vaiman said the circulation of information “involving war or conflict,” coupled with Polymarket’s anonymity, “can create incentives for informed participants to act early.”

Back in January, analytics firm Polysights also noted an apparent spike in bets around the likelihood that Iran’s now-deceased Supreme Leader Ali Khamenei would no longer hold that role by the end of March.

Responding to concerns that such bets might essentially place a financial incentive on assassination, Kalshi CEO Tarek Mansour said, “We don’t list markets directly tied to death. When there are markets where potential outcomes involve death, we design the rules to prevent people from profiting from death.” He added that Kalshi would reimburse all fees from these bets.