The move could shutter the country’s largest opposition party, the Islamic Action Front, which is the Brotherhood’s political arm in Jordan.

Jordan has announced a sweeping ban on the Muslim Brotherhood that could include shutting down the country’s largest opposition party, after accusing the Islamist group of planning attacks.

Jordan’s government on Wednesday formally outlawed the Muslim Brotherhood—the country’s most organized opposition movement—and moved to seize all of its property, Interior Minister Mazen Fraya announced.