Bomb smuggled into Iran guesthouse months ago killed Hamas leader

Mourners for Ismail Haniyeh, a top political leader of Hamas, at his funeral Thursday in Tehran, Iran. (Arash Khamooshi/The New York Times)

Ismail Haniyeh, a top leader of Hamas, was assassinated Wednesday by an explosive device covertly smuggled into the Tehran, Iran, guesthouse where he was staying, according to seven Middle Eastern officials, including two Iranians, and a U.S. official.