Katharine Lackey and Oren Dorell

USA TODAY

Reports that 11 commercial jetliners are missing from the main airport in Libya's capital of Tripoli are raising fears that militants could use them in terrorist attacks to mark the 13th anniversary of 9/11 next week.

The Washington Free Beacon, a conservative news website, cited anonymous sources who said intelligence agencies have warned the jets could be used in attacks in North Africa and elsewhere on Sept. 11.













The date also marks the second anniversary of the Libyan terrorist attack on the U.S. diplomatic compound in Benghazi that killed four Americans, including Ambassador Christopher Stevens.

State Department spokeswoman Marie Harf said, "We have nothing to confirm these reports about missing airliners."

A spokeswoman for the White House National Security Council, Bernadette Meehan, also said there's been no confirmation that aircraft had been stolen.

Images have surfaced online showing militants posing with the jetliners taken when the militants overran Tripoli's airport last month in a fierce battle that left much of the airport and its aircraft damaged.

In the past four months, a renegade general has battled Islamic militants in the eastern city of Benghazi — cradle of the 2011 uprising that toppled Moammar Gadhafi — as powerful regional militias have fought for control of the Tripoli airport. Islamist-allied militias have seized virtually all of the capital.

Moroccan military expert Abderrahmane Mekkaoui said there was "credible intelligence" that one Libyan militia "is plotting to use the planes in attacks on the (region) on the 9/11 anniversary," The Huffington Post reported, citing Al Jazeera television.

An aviation security expert said the planes, if actually seized by terrorists, would pose more of a threat to countries near Libya than the U.S. homeland.

Any stolen aircraft from Libya would unlikely penetrate post-9/11 U.S. air defense and security measures, but they could pose a threat to targets that are much closer, said Jeffrey Price, author of Practical Aviation Security and professor at Metropolitan State University in Denver.

Airliners are required to file flight plans before entering U.S. airspace, and air-traffic monitors would be looking for aircraft matching the description of any stolen planes, Price said. An airliner could try to fly below radar to avoid detection, but the U.S. military has developed systems to detect and stop low flying threats, he said.

Price said most countries near Libya, including in Europe, do not have the same air-defense capabilities and would be more at risk.

The reports of the missing planes, which first surfaced in mid-August, likely sparked an international search for the planes by intelligence agencies, Price said. "It's hard to hide a big jet," he said.

The latest report surfaced after an Islamist militia seized a U.S. Embassy residence in Tripoli last weekend, posting video online of men playing in a pool at the compound. In late July, U.S. diplomats evacuated the compound and the capital and traveled to neighboring Tunisia under a U.S. military escort as fighting between rival militias intensified and thousands fled.

About 150,000 people have fled Libya during the fighting and another 100,000 have been internally displaced, according to a United Nations report released Thursday.

Contributing: The Associated Press