|The discovery of the bodies of Reyes' relatives has led surviving family members to demand justice [EPA]
Mexican police has discovered the bodies of three people related to a human rights activist who was killed last year in the northern Mexican border State of Chihuahua.
The bodies of a sister and brother of Josefina Reyes and her sister-in-law were found on Friday in the desert southeast of Ciudad Juarez, Nicolas Gonzalez, general attorney for Ciudad Juarez, said.
The three had been missing since February 7, when witnesses reported that armed men forced the trio from a vehicle near Ciudad Juarez, across from El Paso in the US state of Texas.
Their bodies were found with a written message from their alleged killers, but officials did not reveal its contents.
The discovery has led surviving relatives to demand justice from Felipe Calderon, the Mexican president.
They urged him to act with the same determination used to pursue the killers of Jaime Zapata, a US immigration and customs enforcement (ICE) agent who was fatally shot in northern Mexico on February 15.
The Mexican army, on Wednesday, detained Julian Zapata Espinoza, an alleged drug trafficker, and two other men in connection with the shooting, which also wounded Victor Avila, another ICE agent.
"Just as he solved the crime against Zapata, I want him to solve the crime against my siblings," Claudia Reyes, a sister of the victims, said at a protest site set up in front of the senate in Mexico City.
The family said they would continue to demand justice, despite concerns for their safety.
Josefina Reyes was slain a year ago in Ciudad Juarez. She had led protests against alleged abuses by Mexican soldiers in the Juarez valley.
Last August, unknown assailants killed her brother Ruben. Earlier this month, the home of Reyes' mother, Sara Salazar, was set on fire while she was protesting against the crimes on her family.
The Reyes family's case has led organisations such as the UK-based Amnesty International to urge Mexico to protect the safety of human rights activists.
More than 3,100 violent deaths were registered in Ciudad Juarez in 2010 alone, in a region at the heart of Mexico's brutal drug violence.
In another incident on Friday, the mayor of a town in northeast Mexico survived an apparent assassination attempt after his bodyguards repelled the attackers in a gunfight.
It left three armed men dead. Two of the attackers, including a woman who was injured in the shootout, fled the scene and were later detained.
Jaime Rodriguez, the mayor, escaped injury in the attack, which occurred in the town of Garcia, a suburb of the northern industrial hub of Monterrey, which has seen a surge in drug cartel-related violence.
Rodriguez said he owes his life to his police bodyguards, who returned fire from his bulletproof 4WD vehicle and repelled the attack.
"Today, I owe them my life, they saved me,'' Rodriguez said of the bodyguards, none of whom was injured.
Rodriguez said he was traveling from Garcia to Monterrey for a meeting when the assailants opened fire from another sport utility vehicle.
Rodriguez says former police officers were responsible for a previous attack on his town's police, but said he did not know if they were also responsible for Friday's attempt on his life.
In yet another incident, a special squad of armed police in Garcia had come under fire late on Thursday night from a group led by three ex-police officers working for organised crime.
There were no injuries or arrests.
Rodriguez said he had fired the former police officers after they failed anti-corruption checks.
Separately, the governor of the Gulf coast state of Veracruz reported on Friday that another mayor in his state was missing since he set off on a trip to neighbouring Tamaulipas state on Wednesday.
Drug cartels have been waging bloody turf battles in Tamaulipas.
At least thee mayors have been assassinated in Mexico so far in 2011, and more than a dozen were killed in 2010. The country has about 2,440 mayors.
Many of the killings were allegedly linked to organised crime, but police officers angered by efforts to clean up local forces have also been implicated in some attacks.