Discovery of three suspicious bags with box cutters and other items on two Southwest Airlines jets prompted federal officials to order a search of every airliner in the nation within 24 hours.

The bags, left on planes in Houston and New Orleans last night, were accompanied by notes expressing concern for security on airplanes, Fox News reported. Along with the box cutters, they contained a claylike material and bleach.

A U.S. official said there is no apparent connection to terrorism.

Nevertheless, Department of Homeland Security spokesman Brian Roehrkasse said the federal Transportation Security Administration has ordered the search of all commercial aircraft.

Box cutters were believed to have been used as weapons by the hijackers who overtook airline crews in the Sept. 11, 2001, terrorist attacks on New York and the Pentagon.

One week ago, federal authorities distributed a special bulletin to law enforcement officials nationwide warning of possible terrorists attacks on the United States.

“Recent multiple reports indicate terrorists may be poised to conduct simultaneous attacks in the near term against U.S. interests in a number of venues overseas and possibly in the United States,” the dispatch said.

Southwest Airlines said maintenance workers in New Orleans discovered a small plastic bag last night on a plane from Orlando, Fla. A check on a plane at Hobby Airport in Houston, which arrived from Austin, revealed a similar package.

“A note in both packages indicated the items were intended to challenge the Transportation Security Administration (TSA) checkpoint security procedures,” Southwest said in a statement.

A check of the airline’s 385 aircraft turned up no related items.

“We will not speculate on who might have left these items onboard. We will cooperate with the federal authorities to investigate this thoroughly,” the statement said.

FBI Director Robert Mueller said the Joint Terrorism Task Force is examining the finds, but stated, “I think it’s safe to fly.”

Some of the FBI’s 84 joint terrorism task forces are handling the probe, along with DHS, Fox News said.

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