"The U.S. has intercepted an order from Iran to militants in Iraq to attack the U.S. Embassy and other American interests in Baghdad in the event of a strike on Syria," The Wall Street Journal reports.

Citing "U.S. officials" as its sources, the Journal says the intelligence is among "an expanding array of reprisal threats across the region. It adds that "U.S. officials said they are on alert for Iran's fleet of small, fast boats in the Persian Gulf, where American warships are positioned. U.S. officials also fear Hezbollah could attack the U.S. Embassy in Beirut."

Iran, along with Russia, China and the Lebanon-based Shiite militant group Hezbollah, is among the relatively few "friends" still supporting Syrian President Bashar Assad. As the Parallels blog has explained, "their relationship dates back to the years after the 1979 Islamic revolution in Iran."

NPR has not independently confirmed the Journal's report.

Meanwhile, as NPR's Scott Horsley reports from St. Petersburg, Russia, President Obama will use the second and final day of the G-20 Summit of world leaders to continue pressing for support of his plan to strike Syria. Obama believes Syrian President Bashar Assad's regime must be held accountable for a chemical weapons attack near Damascus last month that the U.S. believes killed more than 1,400 people.

In between meetings with other leaders, Scott adds, Obama has also been calling members of Congress to lobby for their support. The president has said that while he reserves the right to go ahead and use force, he wants a green light from Congress because that would signal to the world that the U.S. is united on the need to take action.

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