At least 16 miners lost their lives after being buried last week beneath a mudslide at an illegal gold mine in Colombia’s southwestern state of Cauca.

Over the weekend, authorities directing search and recovery operations at the site ruled out any survivors among missing miners, who are trapped under some 20 meters of debris. “It is hard to imagine that we'll find survivors, given that about 10 tons of earth fell on the victims,” local rescue coordinator Graciela Tovar told the AFP news agency.

As of Monday, the bodies of 12 victims had been found; five of them were women. Four more workers remain missing. Hundreds of residents of the area have come to the mine site in desperate hope that someone will be pulled out alive, ignoring warnings from emergency workers that they themselves could fall victim to another slide.

Entire families worked in the mine. One of them, the Cabalis family, reported five members—three men and two women—taken away by the collapse.

The disaster struck at about 11:30 p.m. Wednesday night, when a wall of earth collapsed, trapping the miners in the dark open pit where they worked as much as 30 meters beneath the surface.

As many as 1,500 people are employed in some 50 illegal open pit gold-mining operations in the same area, and as many as 6,000 in the southwestern region of the country.

Many are drawn into the mining operations, which provide absolutely no safety for the workers, out of poverty and inability to find work elsewhere paying a livable wage. “Because of the economic situation, you have to find some way to support your children,” one of the surviving miners, Ofir Balanta, told the Colombian daily El Tiempo .

Local residents recounted that the mine was run by a wealthy “mafia” which employed impoverished peasants as well as workers who came from nearby towns in search of a paying job. According to some, the mine owners used a portion of the profits to pay protection to both government officials and the FARC (Revolutionary Armed Forces of Colombia) guerrillas. They also maintained their own armed security to intimidate workers, local officials and area residents.

The right-wing government of President Juan Manuel Santos has tried to blame the illegal mining operations on the guerrillas. The reality, however, appears to be that well-connected criminal operations that previously directed Colombia’s cocaine trade have at least in part shifted to mining because it can offer greater profits.

For the government, the issue is not one of workers’ safety, but rather of its deals with transnational mining companies. The Cali-based daily El Pais quoted sources close to the National Mining Agency as saying that the area where the disaster had taken place was turned over as a 30-year concession to the South African-based AngloGold Ashanti. The global mining firm had sought to get out of the deal, claiming a lack of security for its operations.

During a visit to the site of the catastrophe, Colombia’s deputy minister of mining, César Díaz, affirmed that “none of the operators here are the ones who have the mining title.” He claimed that, “if these activities were formal, they would have the full oversight of the National Mining Agency.” The reality of mining in Colombia is one of extreme danger and a high death toll for both legal and illegal operations.

So far this year, the government has officially recorded 43 miners’ deaths, 30 of them having taken place in illegal or informal mines. Just days before the latest disaster, four miners died in the northwestern department of Antioquia from inhaling toxic gas at an informal mine.

At least half of Colombia’s 14,000 mines operate without legal permits. Nonetheless, corporate mining dwarfs the illegal and informal operations in terms of volume of production as well as the destruction it inflicts upon the country’s environment.

In the first nine months of 2013, Colombia recorded $2.3 billion in foreign direct investment in the mining sector, a 21 percent increase over the previous year.

“Our goal is to keep promoting a reliable climate for responsible and sustainable mining activity,” President Santos told investors at a recent mining conference in the Caribbean city of Cartagena. At the same time, he vowed to continue a crackdown against the smaller illegal and informal operations.

In July of last year, workers in the informal and illegal mining sector staged a nationwide strike to protest the government’s repression. The government formally agreed to initiate legislation officially recognizing the sector and drawing up guidelines for how it should be treated by officials and for environmental regulations. While representatives of the miners participated in talks, no concessions were forthcoming from the government, which has continued to mount police raids.

Some of the miners are joining an ongoing nationwide strike by farmers over the failure of the government to comply with agreements reached following a strike in the agricultural sector last year.

The mounting social conflicts are developing in the run-up to a May 25 national election in which Santos is seeking reelection. He barely leads his challengers, polling just 32 percent support.