Top Mexican official resigns

MEXICO CITY - Mexico's attorney general has stepped down, in an apparent attempt to free President Vicente Fox's government from a controversial legal battle with a popular leftist mayor.
Rafael Macedo de la Concha led a campaign that stripped Mexico City Mayor Andres Manuel Lopez Obrador of immunity so he could stand trial on charges that he defied court orders in a land dispute.
If Lopez Obrador is found guilty, he could be blocked from running in next year's presidential election.