(CNN) -- Mexico's top security official says the Sinaloa drug cartel was likely behind the kidnapping of a group of four journalists, two of whom were freed in a police rescue.
The kidnappers wanted to use the reporters, who were connected with some of Mexico's largest news organizations, to force the media to transmit "criminal messages," Mexican Public Safety Secretary Genaro Garcia Luna told reporters Saturday.
A federal police rescue freed two of the four journalists, who were kidnapped Monday while covering a riot at a prison in the northern state of Durango, Garcia Luna said. A third was released Thursday. But the whereabouts of the fourth reporter were unclear Sunday.
The two rescued journalists sat beside Garcia Luna and described their captivity to reporters Saturday.
"It is a sad and bitter experience that nobody wants even the worst of their enemies to go through," Multimedios camerman Javier Canales said, noting that he suffered psychological abuse and threats.
"Since the moment they took us, we thought they were going to kill us," Televisa Laguna photojournalist Alejandro Hernandez said, according to state news agency Notimex.
Their kidnapping was a high-profile reminder of an issue that has been increasingly common amid Mexico's escalating drug war: violence against the journalists who cover it.
The journalists were kidnapped Monday while reporting on a protest by inmates and relatives at a local prison, which made news after Mexico's Attorney General's office revealed guards there let free a squad of imprisoned hit men to carry out a massacre of 17 people in a nearby town.
The journalists were abducted in the Laguna region, Mexico's National Commission for Human Rights said -- an area which has been the scene of vicious fighting between the Zetas crime group and the Sinaloa cartel. It includes the state of Durango and parts of neighboring Coahuila.
On Friday, the signal of one of Mexico's largest television networks faded to black for almost an hour as a symbolic protest.
"We will not pretend that nothing is happening," said Denise Maerker, anchor of Televisa's "Punto de Partida" as she opened the show.
Critics have said the government does not do enough to hold criminals accountable.
On Friday, Mexico City's Milenio newspaper published an editorial calling on the government to step up its game to solve the hostage situation. In the editorial, journalist Ciro Gomez Leyva alluded to demands from the kidnappers for the media to publish certain images in return for the release of the journalists.
"That is not our duty. The media is not designed nor equipped to negotiate in a hostage situation," Gomez wrote.
Garcia Luna said Saturday that investigations would continue to determine who was responsible.
"The Mexican state is above any criminal organization or group and is much stronger than these organizations," he said.
The powerful Sinaloa cartel, which Garcia Luna said may have been behind the kidnapping, transports multi-ton quantities of drugs from Mexico to the U.S., according to the Drug Enforcement Administration.
Forbes magazine has estimated the fortune of its leader, Joaquín "El Chapo" Guzmán Loera, at $1 billion. He escaped from a Mexican prison in 2001.
CNN's Krupskaia Alis and Gustavo Valdes contributed to this report.