SAN DIEGO (CNS) - A man's report of finding an unidentified package stuck to the undercarriage of his SUV at a Serra Mesa gas station Monday morning prompted authorities to cordon off the area until a bomb squad determined that the object contained what appeared to be some type of illicit drug.

The motorist made a 911 call about 9 a.m. to report the discovery in the 3600 block of Murphy Canyon Road, police said. He told a dispatcher he had removed the object and placed it on a passenger seat.

Ordnance-handling personnel investigated, eventually determining that the package was non-explosive but filled with an apparent controlled substance, said Lee Swanson, a spokesman for the San Diego Fire-Rescue Department. It had been attached to the vehicle with a magnet.

Officials gave an all-clear and reopened the site to the public shortly before 10:30 a.m., Swanson said.

Police were questioning the owner of the SUV to try to determine how the package wound up attached to his SUV. The man had recently been to Mexico, leading authorities to believe it might have happened there, Swanson told reporters.