Former Guatemalan President Otto Perez Molina and his then-vice president led a criminal structure that collected at least $30 million in bribes to award a contract to build a port terminal, the country's attorney general and an international anti-corruption commission announced Friday.

In exchange, Grupo TCQ Terminal de Contenedores Quetzal got to build the terminal at the Pacific coast location of Puerto Quetzal and hold a 25-year concession to operate it worth $225 million, authorities said. Perez Molina signed the contract with the Spanish firm in 2013 while he was president.

"Since Perez Molina was elected in November 2011, the paperwork for this project started quickly," said Attorney General Thelma Aldana. "A criminal group formed ... having Otto Perez Molina and Roxana Baldetti as this structure's leaders."

Judge Miguel Angel Galvez called for Perez Molina and former vice president Roxana Baldetti to appear on money laundering charges next week.

A son-in-law of Perez Molina was detained Friday for allegedly participating in the scheme, as well as Juan Jose Suarez, manager for the company TCQ.

Perez Molina is behind bars and faces charges of permitting and benefiting from a ring that defrauded the state of millions of dollars. Businesses allegedly paid kickbacks to officials in exchange for lower import duties.

Perez Molina has said he is innocent of the charges.