Clapper warns of lone wolf attack

A top U.S. intelligence official recently warned Congress that Iran is now more willing to attack the United States and American interests abroad, but said questioned if any terrorist attack on U.S. soil would make use of chemical, biological or radiological weapons.

In Congressional testimony, Director of National Intelligence James Clapper said that a failed 2011 plot to assassinate the Saudi ambassador to the United States in Washington has convinced the U.S. intelligence community that the Iranian leadership is willing to carry out an attack on U.S. soil, according to the Boston Herald.

"Some Iranian officials - probably including Supreme Leader Ali Khameni - have changed their calculus and are now willing to conduct an attack in the United States," Clapper said in a written statement to the Senate Select Committee on Intelligence, the Boston Herald reports.

Clapper also said that Tehran is continuing with plans to develop weapons-grade nuclear material.

The aggressive campaign of airstrikes against al-Qaeda appears to have degraded the terrorist group's senior leadership to the extent that Clapper said that it may cease to be the most significant threat facing the United States in the near future.

Clapper said "lone actors" and "criminals" may attempt to conduct an attack on the United States within the next year, but added that they would most likely not be part of a larger terrorist network.