Notorious drug lord Joaquin "El Chapo" (Shorty) Guzman is escorted to a military helicopter after being recaptured in January. EFE/File

A general view of the headquarters of the lawyers firm Mossack Fonseca in Panama City, Panama, 4 April 2016. The massive leak of the 'Panama Papers' unveiled a worldwide scandal in which hundreds of leaders, businessmen, and celebrities appeared as beneficiaries of unreported bank accounts in the country. EFE/Alejandro Bolivar

A general view of the headquarters of the lawyers firm Mossack Fonseca in Panama City, Panama, 4 April 2016. The massive leak of the 'Panama Papers' unveiled a worldwide scandal in which hundreds of leaders, businessmen, and celebrities appeared as beneficiaries of unreported bank accounts in the country. EFE/Alejandro Bolivar

A Mexican government contractor, a former CEO of state-owned oil giant Petroleos Mexicanos, or Pemex, and an associate of notorious drug lord Joaquin "El Chapo" (Shorty) Guzman are some of the individuals whose names appear in the Panama Papers.

Mexican media outlets Aristegui Noticias and Proceso magazine, part of the International Consortium of Investigative Journalists, or ICIJ, say that a portion of the roughly 11.5 million confidential papers leaked from Panama-based law firm Mossack Fonseca reveal that Juan Armando Hinojosa, the owner of the Grupo Higa conglomerate, concealed up to $100 million in tax havens.

The effort to hide that fortune through a network of offshore companies began a month after it was revealed that Angelica Rivera, the wife of Mexican President Enrique Peña Nieto, had purchased a mansion from Grupo Higa, which has won lucrative contracts from Peña Nieto-led governments, both at the national level and when he was governor of the central state of Mexico.

The investigation spearheaded by the ICIJ and published Sunday based on the massive leak of confidential documents, known as the Panama Papers, found that Hinojosa, as part of his efforts to conceal his assets, created five companies in his mother's name and registered them in the British Virgin Islands.

Former Pemex CEO Emilio Lozoya, for his part, appears in a 2011 document expressing interest in creating a company with Mossack Fonseca, although there is no indication that any entity was established.

In a statement, Lozoya "categorically" denied having registered companies in Panama, holding bank accounts in that country or maintaining any relations with Mossack Fonseca.

The investigation published by Aristegui Noticias and Proceso also discovered links between that Panama-based law firm and drug cartels.

For instance, Mossack Fonseca created a company in 2007 but then dissolved it a month later after the U.S. Office of Foreign Assets Control linked it to Colombian drug trafficker Jorge Milton Cifuentes, an associate of El Chapo, the imprisoned leader of the Sinaloa drug cartel.

Also appearing in the Panama Papers are two well-known Mexican media executives: Alfonso de Angoitia, an executive vice president of No. 1 broadcaster Televisa; and Ricardo Salinas, the founder and chairman of No. 2 broadcaster TV Azteca and one of Mexico's wealthiest individuals, according to Aristegui Noticias and Proceso, which were among the global team of journalists that investigated the 2.6-terabyte leak.

Salinas, according to the investigation, used offshore companies to, among other things, buy works of art.

The media executive's public relations team issued a statement saying he has always acted "in strict accordance with the law."