MADRID (Reuters) - Four members of a major Mexican drug-trafficking cartel have been arrested in Madrid, including a cousin of Mexico's most wanted man.
The Sinaloa Cartel, one of the biggest criminal organizations in the world, was trying to set up a European operation based in Spain, Spain's Interior Ministry said in a statement on Friday.
"Our country was going to be used as a point of entry for large shipments of narcotics," it said.
One of the four Mexican men arrested was named as Jesus Gutierrez Guzman, a cousin of Joaquin "Shorty" Guzman, the head of the cartel.
All four men, who were arrested near hotels in central Madrid, are wanted in the United States over allegations of drug trafficking and money laundering.
The arrests were part of a joint operation with the U.S. FBI dubbed Dark Waters, which began in 2009. Spanish officials involved in the operation seized a container with 373 kg (822 pounds) of cocaine in the port of Algeciras in July.
The news caused a splash across Mexican media when it emerged that one of the suspects was linked to Mexico's Institutional Revolutionary Party, or PRI, whose candidate won July's presidential election.
Rafael Celaya had applied to be a PRI candidate for federal deputy for the northern state of Sonora in the July poll, but was unsuccessful, according to the official party website.
A photo on Celaya's Facebook page showed him standing next to incoming president Enrique Pena Nieto at a campaign event.
The PRI released a statement on Friday confirming that Celaya had been rejected as a candidate and saying he had no special connection with Pena Nieto.
"During his campaign for presidency, Enrique Pena Nieto took hundreds of thousands of photos with militants and sympathizers but that doesn't imply any commitment or alliances," it said in the release.
(Reporting by Fiona Ortiz; Additional reporting by Lizbeth Diaz and Anahi Rama in Mexico City; Editing by Julien Toyer, Pravin Char and David Brunnstrom)