Abbottabad, Pakistan (CNN) -- After a day of international exaltation over the death of Osama bin Laden, questions remain about who might take over his terrorist group and whether a trove of material gathered from bin Laden's compound might tip off U.S. officials to other al Qaeda leaders and plots.
But already, at least one threat of revenge has surfaced against the United States, which carried out the mission to eliminate bin Laden.
"We are proud on the martyrdom of Osama," Ahsan Ullah Ahsan, spokesman for Tehrik-e-Taleban Pakistan (TTP), said late Monday night. "We shall definitely take revenge (on) America as well as Pakistan, as they aided Americans in this operation. All the government functionaries are on our hit list. We shall never spare any one of them."
When asked how the Pakistani Taliban organization would carry out revenge on America, Ahsan said, "We already have our people in America, and we are sending more there."
Earlier, CIA director Leon Panetta said in a message to agency employees that terrorists "almost certainly" will attempt to avenge bin Laden's death.
U.S. diplomatic facilities around the world have been placed on high alert following the announcement of bin Laden's death, a senior U.S. official said, and the U.S. State Department issued a "worldwide caution" for Americans.