terror attacks

The U.S. said the number of global terrorist attacks declined slightly between 2014 and 2015, although the Islamic State group expanded its reach. Iran remained the leading state sponsor of terrorism despite sealing a nuclear deal with world powers, the State Department said in its annual survey of worldwide terrorism released Thursday.

Investigators say they are still looking for at least one suspect in the attacks seven days ago, when suicide bombers killed 32 people at Brussels' airport and in a subway station near the European Union headquarters. Three suicide bombers also blew themselves up.

Belgian authorities searched Wednesday for a man pictured at the Brussels airport with two apparent suicide bombers, amid growing suggestions that the bombings of the Brussels airport and subway were the work of the same Islamic State cell that attacked Paris last year.

Mason Wells, a 19-year-old from Sandy, Utah, is expected to make a full recovery, after the bombing at the Brussels airport Tuesday left him with a surgery scar, a severed Achilles tendon, a head gash, shrapnel injuries and severe burns.

As efforts to clamp down on ISIS continue following the terror attacks in Paris, the U.S. Department of Homeland Security is maintaining an elevated state of alert, which means there is a significant risk of a terror attack somewhere in America.

Extremists in Iraq, Afghanistan and Nigeria unleashed a savage rise in violence between 2013 and 2014, according to new statistics released by the State Department. Attacks largely at the hands of the Islamic State and Boko Haram raised the number of terror acts by more than a third, nearly doubled the number of deaths and almost tripled the number of kidnappings.