SAN DIEGO -- A man was sentenced Thursday to 25 years in federal prison for his role in the kidnapping and slaying of a San Diego private investigator who was brutally beaten in Mexico for five days before being killed.

Humberto Iribe pleaded guilty May 22 to conspiracy and attempted kidnapping in connection with the August 1998 kidnapping and slaying of Richard C. Post III, 54, of San Diego.

A federal grand jury indictment alleged that Iribe conspired with Kimberly Bailey of Fallbrook and John Krueger of San Diego to kidnap Post III and take him to Mexico. The indictment alleged that Iribe and the others planned to beat and torture Post until he disclosed where certain money and property was located in the United States.

According to a plea agreement, Iribe admitted that he and his men held Post hostage in Mexico and beat him for about five days. Iribe further acknowledged that the government could prove that he and his associates later killed Post.

In August 2003, Bailey was sentenced to life in prison for Post's kidnapping and murder, after a federal jury convicted her of conspiracy and other charges. Krueger pleaded guilty to conspiracy to kidnap a person in a foreign country and was sentenced to 12 years in federal prison.