Rescuers are using spades and ropes to search for survivors after an illegal gold mine collapsed on the Indonesian island of Sulawesi, trapping more than 60 people, according to authorities.

"When dozens of people were mining for gold at the location, suddenly beams and supporting boards they used broke due to unstable land and numerous mining shafts," disaster agency spokesman Sutopo Purwo Nugroho said Wednesday morning.

"Evacuation efforts continued through the night because of the number of people estimated to be buried," he added.

Rescuers said they could hear the voices of some of those trapped inside.

"We are able to detect that many of them are still alive because we can hear their voices, as there are some places where air is getting in and out and there are gaps in the mud," Abdul Muin Paputungan of Indonesia's disaster agency told the Reuters news agency.

Gold fever in Lombok Joining the gold rush The gold mining boom on the Indonesian island of Lombok has radically changed the economy of a region that once depended on fishing and farming. The thriving industry is helping locals like Rizki (pictured) make a living. At his shop, the 30-year-old jeweler from Sekotong Province sells gold at 250,000 rupees (about $20/15 euros) per gram.

Gold fever in Lombok A dangerous substance Although the use of mercury in gold mining is illegal in Indonesia, it is routinely used to extract gold in Lombok. Every year, tens of tons of mercury are released into the environment. Above, a gold dealer points out the amalgam before (grey item) and after (gold item) the mercury is burnt out. This is the most dangerous stage of mining, because mercury can be absorbed into the body.

Gold fever in Lombok Hills like Swiss cheese The growth in mining has seen most of the hills in Sekotong province become overrun with holes and a dense network of tunnels. Small huts covered with blue tarpaulins mark the entrances to the tunnels on this slope near the village of Pelangan. The hundreds of meters of passageways were dug by hand, without the use of proper mining techniques or equipment.

Gold fever in Lombok Life in the mines Using a small chisel, miner Saiful, aged 48, spends his days filling up 30-kilogram (66 Pound) bags with raw ore. "I start early morning and I don't stop until sunset," he says. "The more bags you fill, the more you want to keep digging because you don't know how much gold will be in one bag."

Gold fever in Lombok Cramped conditions The tunnels are just wide enough to allow a man to crawl through. "Sometimes, when we dig our tunnel, we end up inside a friend's tunnel, so we just come back a little and start digging in another direction," says Saiful. The only light comes from a small headlamp worn by the miners, and temperatures can reach 38 degrees Celsius.

Gold fever in Lombok Golden hopes Many impoverished families have tried their luck in Lombok's lucrative gold business. In the village of Pelangan, 29-year-old Dewi is extracting the steel bars from the grinder after three hours of smashing the ore to turn it into mud. The grinders are kept in the same shelter where the family sleeps, eats and lives. Dewi's daughter, just arrived home from school, watches her work.

Gold fever in Lombok Mercury risk In another Lombok village called Telage Lebur, 18-year-old Mashur separates the sludge from the mercury bound to gold. He has been working as gold miner and processor since he was 14. Neither he, nor his family, are aware of the risks of handling liquid mercury without protection. Mercury can harm people's nervous, digestive and immune systems, as well as their lungs, kidneys, skin and eyes.

Gold fever in Lombok Controversial cyanide Using cyanide to extract fine gold from ore is a controversial process, because cyanide is a highly poisonous chemical compound. At this cyanidation site in the village of Tawun, sediments are mixed with water directly to be turned into slurry again and be pumped into the reaction silos for processing.

Gold fever in Lombok The ecological cost The plant is next to a canal that runs into the sea and through a mangrove forest, yet it has neither protection nor barriers to prevent environmental pollution. The water in the island's cyanidation sites is contaminated with mercury and cyanide, and is highly toxic for wildlife in the area.

Gold fever in Lombok Health hazard The chemicals used to mine gold aren't only dangerous for the environment - they also pose serious risks to the health of people on the island. Agis, 12, stands on the former site of a cyanidation plant in the village of Gili. The village's rice fields and soil were polluted by the toxins. In 2012, the mercury concentration in Agis' hair was double the World Health Organization's standard. Author: Elisabetta Zavoli



Illegal mines prone to accidents

One person has been found dead and 13 were rescued by 5 a.m. local time on Wednesday.



The mine is located in the Bolaang Mongondow area of North Sulawesi province, about 3,000 kilometers (1,800 miles) northeast of Indonesia's capital, Jakarta.

Small-scale mining operations are banned in Indonesia, but regional authorities have not cracked down on the practice in remote rural areas. A lack of regulation has made these illegal mines more prone to accidents.

jcg/cmk (dpa, Reuters)

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