(MARATHON, Fla.) - A bomb blew up a car at an intersection Wednesday morning, critically injuring the woman driver.
The 8:40 a.m. explosion blew a hole in the four-door Saturn's undercarriage, blasted away chunks of pavement and damaged a nearby vehicle, said Becky Herrin, a Monroe County Sheriff's spokeswoman.
Initially, officials suspected there was another bomb in the car that had not exploded, but no other devices were found and by midday bomb squad officers cleared the way for investigators to begin combing the car for clues, said Herrin.
The 51-year-old Marathon woman, whose identity was not immediately released, was airlifted to Jackson Memorial Hospital and was in critical condition, said hospital spokeswoman Lorraine Nelson.
The blast shut down U.S. 1, the only highway linking the Florida Keys south of Key Largo.
The sheriff's office was awaiting assistance from the FBI and Miami-Dade County Police, Herrin said.