The paper advocated judicial and tax reforms, and reported on dangerous subjects including narcotics smuggling, human rights issues, guerrilla groups, and corruption in the government of President Jorge Serrano.

[1] Zamora's new newspaper, El Periódico, launched on November 6, 1996, funded by the donations of 125 citizens who supported his stand on press freedom.

[1] In 2001, the Periódico offices were attacked by a group of fifty protesters after reporting on alleged corruption in the staff of Communications Minister Luis Rabbé.

[5] The newspaper conducted a lengthy investigation into links between the government of President Alfonso Portillo and organized crime, the results of which were published in November 2002.

In 1995, his car was driven off the road by two people who threatened to kill him for publishing allegations in Siglo Veintiuno that the military of Guatemala had links to organized crime.

[6] Portillo then unexpectedly visited Zamora to offer assistance, including allowing him access to a photographic database of government and armed forces members.

In late January 2004, Zamora published the names and photographs of the men and woman he alleged to be his attackers in El Periódico; they included a senior member of Portillo's staff, an employee of the Attorney General, and a counter-intelligence specialist.

[9] On August 20, 2008, Zamora was kidnapped and beaten after a dinner with friends in Guatemala City, and was left unconscious and nearly naked in Chimaltenango, 25 kilometres (16 mi) away.

[11] In the same year, he won the Maria Moors Cabot Prize from Columbia University "for promoting press freedom and inter-American understanding".

[2] The citation stated that "Zamora and Siglo Veintiuno were in the forefront of a civilian resistance that forced President Jorge Serrano Elias to relinquish his post after he attempted to seize dictatorial power in 1993.

However, his arrest was widely seen as a retaliation against his coverage of corrupt practices by the Guatemalan government under president Alejandro Giammattei[15] and was criticized locally and internationally by journalists, freedom of the press activists, political opposition in Guatemala, human rights NGOs, the business sector, the United States, Canada, and the European Union.