Obama says al Qaeda still greatest threat to U.S.

SHANGHAI (Reuters) - U.S. President Barack Obama said on Monday the greatest threats to the United States continued to be terrorist networks like al Qaeda.

"I continue to believe that the greatest threat to the United States' security are the terrorist networks like al Qaeda," he told students at a town hall meeting in Shanghai. "They have now moved over the border of Afghanistan and are in Pakistan, but they continue to have networks with other extremist organizations in that region and I do believe it is important for us to stabilize Afghanistan."

(Reporting by Patricia Zengerle and Caren Bohan; Writing by Chris Buckley; Editing by Jerry Norton and Jeremy Laurence)