WASHINGTON — Intrade, the online prediction market that gained popularity as an informal oddsmaker for the presidential election, shut itself to US customers Monday after regulators charged it with illegally facilitating bets on future economic data, the price of gold, and even acts of war.

Hours after the Commodity Futures Trading Commission filed a complaint in federal court, Intrade posted in its user forum and on its news page that it could no longer allow US residents to trade ‘‘due to legal and regulatory pressures.’’