RAUL LLAMAS
  Associated Press

  NUEVO LAREDO, Mexico - State police officials said Friday that a U.S. investigation of the busy U.S. consulate in this border town apparently is centered on a woman accused of selling U.S. visas for $1,900.

  State police said complaints were filed here last year against Margarita Martinez Ramirez, alleging she failed to deliver a visa after accepting payment.

  Many others did receive visas, however, according to the El Diario newspaper, which said Martinez, who did not work at the consulate, sometimes met visa customers at a local Church's Chicken restaurant and split her fee with Mexicans employed by the consulate.

  Neither U.S. nor Mexican investigators have been able to locate her recently, according to police.

  Spokesmen at the U.S. Embassy in Mexico City said they could not comment on the case while it was under investigation.

  The visa section of the U.S. consulate in Nuevo Laredo was closed Wednesday and was to remain closed at least through next week to investigate visa operations. Thomas Armbruster, the consul general in Nuevo Laredo, said the roughly 30 Mexican citizens working at the consulate were being interviewed by U.S. investigators from Washington, Mexico City and Monterrey.

  U.S. State Department spokesman Richard Boucher said Wednesday investigators were looking into "allegations that a number of individuals received visas illegally from this consulate," but he did not provide details.

  A state police commander said Martinez apparently had been selling visas for at least four years.

  The Laredo Morning Times, meanwhile, reported that residents of the Colonia Solidaridad in Nuevo Laredo, across the border from the Texas city, said they had been
  offered legitimate U.S. border crossing cards for $400.

  Security workers at the consulate said at least three Mexican employees of the consulate - two in the visa section and one guard - had been taken across the border for
  questioning.