"We're asking for more resources from mining companies and the federal government because safety conditions at the mines have not improved," said Bishop Alonso Garza of the city of Piedras Negras, close to the border with Texas.
 
Earlier, about 100 relatives and friends of victims staged an all-night vigil, lighting candles and releasing 65 white balloons at 0215 – the time of the explosion.
 
Recovery work
 
Miners unions want legal action taken
against the mine's owners [EPA/File]
Meanwhile crews continued working underground around the clock to recover the remains of the 63 miners who are still trapped.
 
Their task has been complicated by the presence of methane gas that needs to be ventilated out of the mine.
 
Gilberto Rios Ramirez, a retired coal miner whose son died in the February 19, 2006, accident, said the work was delicate and tricky "because you don't know where a co-worker's body may be located."
 
"What I most want a year after, would be to bring out my son's body, but I cannot because of the conditions inside the mine itself," he told AFP.
 
"Even the most modern equipment in the world would not make that happen; we are working by hand."
 
Buried by thousands of tonnes of rock, officials say many of the bodies may have been incinerated by temperatures which soared to 593C after the gas explosion exactly a year ago.
 
Pressure
 
One year on and many relatives are still
unable to bury their dead [Reuters]
Mining union officials said Monday’s strike to remember the disaster shut down most of Mexico’s mines and metal plants. They said they were hoping to pressure the government to punish Grupo Mexico.
 
The special prosecutor for Coahuila state, where the mine is located, blames Grupo Mexico for allowing a deadly mix of methane, dust and oxygen to build up in the mine.
 
"We are talking about a very rudimentary mine with huge lapses in safety standards made worse by corrupt inspectors who didn't enforce the necessary security," Jorge Rios rold Reuters.
 
He said he would urge judges to arrest five Grupo Mexico employees and six officials from the Mexican labour ministry within the next two months on manslaughter charges.
 
Grupo Mexico, one of Latin America's biggest miners, says the blast was a tragic accident. It says it has compensated victims' families and spent $30 million on trying to find the 63 remaining miners.
 
Coal mining in Coahuila state is largely unregulated and accidents are commonplace.