Rescue workers searched Monday the wreckage of a plane that carried Mexican-American singer Jenni Rivera, a star on both sides of the border whose death shocked Latin music fans and celebrities. Civil Aviation director Alejandro Argudin said the search could take several days and that authorities were trying to determine if the Learjet, made in 1969, carried a black-box flight data recorder. \"We are examining what modifications were made to the equipment to improve the plane and see for sure if a black-box exists or not,\" Argudin told reporters. Revered as the \"Diva de la Banda,\" Rivera was among seven people aboard the plane when it crashed shortly after taking off from the northern industrial city of Monterrey early Sunday, after she had given a show there.She was flying to Toluca, near Mexico City, to participate as a coach in Mexico\'s version of the television singing contest \"The Voice.\" Her California driver\'s license and some of her clothes were found at the crash site, where the wreckage spread over a radius of up to 300 meters (yards) in rough terrain. Born in Long Beach, California to Mexican parents, the 43-year-old mother of five was a star in the northern Mexican music genre known as banda, selling 15 million records and winning Billboard Latin Music awards. She was divorcing her third husband, former baseball pitcher Esteban Loaiza. \"So sad!! Praying for Jenni Rivera\'s children and family and the passengers families. God bless them!! Rest in peace,\" US music and film star Jennifer Lopez wrote in one of the many condolences expressed by people on Twitter.