Thirty-six hours before he was killed by U.S. forces, Taliban Commander Mullah Dadullah said he was training American and British citizens to carry out suicide missions in their home countries, according to a videotape interview to be broadcast on ABC News’ "World News" Monday. "We will be executing attacks in Britain and the U.S. to demonstrate our sincerity," he told an Afghan interviewer, "to destroy their cities as they have destroyed our cities." Video Listen to the Taliban Leader’s Final Words. A senior U.S. official told the Blotter on ABCNews.com that recent intelligence reports confirmed Dadullah’s claim that U.S. citizens were being trained in Taliban and al Qaeda camps. "The number is small, not large, but even once is dangerous," the official said. In the interview, Dadullah said, "This is our religious and moral duty to train suicide bombers against the nuclear power of the infidels, and they will be used when they are needed, whether they are one, 10 or 20." Click Here for Full Blotter Coverage. A day and a half after the interview, U.S. forces carried out a helicopter assault on Dadullah’s hiding place in Afghanistan’s Helmand Province. Dadullah’s bullet-riddled body was put on display by Afghan officials to confirm he was dead. U.S. military officials said Dadullah had been tracked from the Pakistani city of Quetta across the border into Afghanistan, where he granted his last interview. "His ego probably got the better of him," said ABC News counterterrorism consultant Alexis Debat. "The U.S. and Pakistan have done an excellent job of intercepting the couriers moving taped messages from al Qaeda and Taliban leaders. This is why we have not seen Osama bin Laden in some time," Debat said.