U.S. issues worldwide terror alert after Iran plot exposed:

U.S. issues worldwide terror alert after Iran plot exposed;
WASHINGTON (AP) — The State Department is warning Americans around the world of the potential for terrorist attacks against U.S. interests following the exposure of an alleged Iranian plot to assassinate Saudi Arabia's ambassador to the United States.

In a new worldwide travel alert issued late Tuesday, the department said the foiled scheme could be sign that Iran has adopted a "more aggressive focus" on terrorist activity. It said Iranian-sponsored attacks could include strikes in the United States, where the alleged plot against the Saudi envoy was supposed to have taken place, as well as other countries.

"The Department of State alerts U.S. citizens of the potential for anti-U.S. actions following the disruption of a plot, linked to Iran, to commit a significant terrorist act in the United States," it said in the warning that expires on Jan. 11, 2012.

"The U.S. government assesses that this Iranian-backed plan to assassinate the Saudi ambassador may indicate a more aggressive focus by the Iranian government on terrorist activity against diplomats from certain countries, to include possible attacks in the United States," the alert said.

Earlier Tuesday, the Justice Department announced the indictment of two men, including an Iranian-born U.S. citizen, for conspiring with a purported Mexican drug cartel to kill the Saudi ambassador on U.S. soil.