Authorities investigating cargo flights in NJ, Pa.

Associated Press

PHILADELPHIA (AP) - Law enforcement officials are investigating reports of suspicious packages on cargo planes in Philadelphia and Newark, N.J.

A law enforcement official briefed on the investigation said officials found something suspicious on a cargo plane in Birmingham, England. But test results for explosives were negative. The official spoke on condition of anonymity to discuss the ongoing investigation.

Transportation Security Administration spokeswoman Kristin Lee says the planes in Philadelphia and Newark landed safely and are being swept by law enforcement.

The planes have been moved to a remote location so law enforcement officials can investigate.

Video from Philadelphia International Airport shows emergency vehicles around a UPS jet.

Associated Press Writer Eileen Sullivan in Washington contributed to this report.

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