Tonight on Special Report with Brit Hume:

Catherine Herridge reports: Three American medical workers are shot and killed, and an American pharmacist seriously wounded, when a gunman opens fire inside a Southern Baptist missionary hospital in southern Yemen.

Guest preview: Joel Wit with the Center for Strategic and International Studies who gives us his take on the situation with North Korea.

Plus:

• The FBI launches a manhunt for several suspected Arab terrorists it says may have entered the United States illegally from Canada last week.

• South Korea is assessing whether communist North Korea was preparing to withdraw from the international treaty that seeks to halt the spread of nuclear weapons.

• U.N. inspectors spend three hours at the Iraqi customs department in their hunt for signs of weapons programs, while a short-circuit at the inspectors' headquarters in Baghdad brings Iraqi firefighters into the normally off-limits hotel.

Details on these stories and more on Special Report with Brit Hume.
— Guests and topics are subject to change