In the last seven years in Mexico, 35 journalists were killed and six went missing, 84 media workers filed complaints of insults or attacks in 2007, and in the first few days of 2008, the prestigious independent radio commentator Carmen Aristegui, who has often criticised the powers that be, was fired.

Given that outlook, many analysts wonder whether the media in Mexico is really as free as the government of conservative President Felipe Calderón claims.

"The record in terms of free speech is not very encouraging, and we see nothing on the horizon that can turn that around; on the contrary, things could get even worse," Aleida Calleja, vice president of the World Association of Community Radio Broadcasters (AMARC), told IPS.

Political scientist José Antonio Crespo at the Centre for Economic Research and Teaching (CIDE) said "many are now wondering uneasily whether we are seeing the beginning of a setback in terms of freedom of the press."

The end of 71 years of rule by the Institutional Revolutionary Party (PRI) in 2000 ushered in greater freedom for the media in Mexico. However, threats to that freedom have not disappeared.

Aristegui, the anchor of the "Hoy por Hoy" news programme at the "W" radio station, announced Friday that it was her last programme after five years on the show. She said the Televisa media giant, which owns the station, had decided not to renew her contract, citing "editorial differences."

Televisa owns 17 radio stations in six Mexican cities, its programming is broadcast over some 90 stations that cover nearly the whole country, and it forms part of Grupo Latino de Radio.

Early this decade, Grupo Prisa from Spain acquired a 50 percent share in Televisa Radio, whose W Radio format is reproduced in Colombia, Chile and Panama, and in the U.S. cities of Los Angeles and Miami.

Aristegui had gained prestige for giving a voice to the left, to social movements and to victims of rights violations, and for fearlessly delving into thorny issues that reflected badly on the Catholic Church and the economic and political elite, including the powerful Televisa and TV Azteca networks, which dominate the market.

Calleja, who used to represent AMARC in Mexico, said Aristegui’s dismissal is part of a process aimed at "silencing the remaining critical, independent voices in the broadcasting media, where freedom is scarce and ownership is heavily concentrated."

Seven out of 10 viewers in Mexico watch channels belonging to Televisa, while two out of 10 watch TV Azteca channels. Meanwhile, just 13 commercial groups own virtually all of the country’s radio stations, although Televisa and Azteca dominate the airwaves.

The situation is different in the print media, where a broad spectrum of options exists, in which the powers that be are criticised with relative freedom.

According to the Calderón administration, in Mexico there is full, unrestricted freedom of speech and the press.

The broad power exercised by Televisa and TV Azteca affects democracy and is not compatible with freedom of expression, "but for now there seems to be no way to put an end to the problem," said Calleja.

In September, the Mexican Congress approved a legal reform that deprived the media giants of the enormous flow of revenues they received in election campaigns through contracts for political advertising.

The legislators also promised that by March 2008, they would have ready a draft law aimed at breaking down the near monopoly enjoyed by the two TV and radio networks. However, there are no clear signs that their pledge will be fulfilled.

In the meantime, the networks have lashed out against lawmakers in favour of the reform.

They also berated the Supreme Court justices who in June declared unconstitutional a law on radio and TV stations approved by the legislature under pressure from the stations, which broadly benefited the powerful broadcasters.

Aristegui, who is also a columnist for the daily newspaper Reforma and who has a talk show on CNN en Español that features in-depth conversations with Mexican leaders from a broad range of fields, had made it clear that she disagreed with her colleagues in Televisa and TV Azteca in their opposition to electoral reforms and to the judges’ resolution, and called for democratisation of the media.

It is up to Televisa to have the anchors it chooses, but not at the expense of freedom of information and of the citizens’ right to hear a wide range of voices, wrote Miguel Granados, a columnist with Reforma and the leftist weekly Proceso.

Aristegui’s departure from Televisa’s "W" radio station merely added fuel to the fire.

The National Human Rights Commission, a government agency, reported that 35 journalists were murdered and six others disappeared between 2000 and 2007. In most of the cases, the journalists had run afoul of drug trafficking gangs because of their reporting.

And last year, the Commission received 84 complaints from journalists who reported insults or aggression in the line of duty, whether by their employers or as a result of their reporting.

"The danger faced by reporters in Mexico is high, as is the impunity surrounding the crimes against our colleagues and the state’s scant or nonexistent interest in clarifying them," said Calleja.

In the Reporters Without Borders’ latest Worldwide Press Freedom Index, released in October in France, Cuba (165th) and Mexico (136th) ranked the lowest in Latin America.