Migrants seeking for refugee status ride on the bed of a trailer in Jesus Carranza, in the Mexican state of Veracruz on November 17, 2021. A group of mainly Central American migrants are attempting to reach the US-Mexico border. Photo: AFP

 The murders of two journalists in the Mexican border city of Tijuana in less than a week have triggered calls for the government to step up protection of media workers.

The killings of photographer Margarito Martinez and reporter Lourdes Maldonado have sparked outcry among colleagues in what is one of the world's most dangerous countries for journalists.

Reporters organized protests on Tuesday in cities across the country, while UN Secretary-General Antonio Guterres urged Mexico to take tougher action.

"We call on Mexican authorities to strengthen the protection of journalists, in particular, to take further steps to prevent attacks on them, including by tackling threats and slurs aimed at them," said Guterres's spokesman Stephane Dujarric.

Martinez, who was shot dead on January 17, and Maldonado, who was gunned down on Sunday, had both requested protection from a security mechanism for journalists in the northwestern state of Baja California.

"The mechanism has failed again when journalists feel most vulnerable," Sonia de Anda, a reporter in Tijuana, told AFP.

Martinez had been threatened by a blogger allegedly linked to criminals, but was still waiting for protection, De Anda said.

Maldonado had been given a police guard for a year when leaving and arriving at her home. But "obviously there were no police" present on Sunday when she was shot outside her house, said De Anda, a member of the media rights group Yo si soy periodista (I am a journalist).

Jorge Carrasco, director of the weekly news magazine Proceso, turned to the mechanism in 2013 after receiving death threats for his work. 

He was assigned a body guard and cameras were installed in his house.

"In my case it worked. But the mechanism was overwhelmed. There were so many cases," he said, alleging insufficient commitment from other state institutions and a lack of coordination with regional authorities. That was a factor in the murders in Tijuana, journalists said.

"Due to a change of governor [in Baja California], the mechanism stopped operating" and was supposed to be reinstated on Monday, said De Anda.

"In the meantime, two of us were killed," she said. 

More than 100 journalists have been murdered since 2000 in Mexico and only a fraction of the crimes have resulted in convictions.