UPDATE 1-Illegal miners at Glencore concession in Congo defy eviction

* Government ordered miners out after deadly landslide * About 2,000 miners operate illegally at the southeastern site

* Some clashes with police as eviction set to begin (Adds union and analyst quotes) By Fiston Mahamba and Aaron Ross

GOMA, Democratic Republic of Congo, July 2 (Reuters) - Illegal miners at a copper and cobalt mine run by Glencore in southeastern Congo defied a deadline on Tuesday to vacate the site, a union official said, raising fears of a potentially violent standoff. A landslide last Thursday at the Kamoto Copper Company (KCC) concession, majority-owned by a Glencore subsidiary, killed 43 people and led Democratic Republic of Congo's government to promise to remove the miners.

The Army's inspector general, General John Numbi, told Reuters on Monday that reconnaissance teams were deployed and an operation to clear the estimated 2,000 miners would begin on Tuesday. Reached by telephone, Joseph Yav, chief of staff to the provincial governor, said police were closing illegal trading houses around the mine and would call on the army if necessary.

But Delphin Monga, provincial secretary of the UCDT union, which represents KCC employees, said illegal miners inside the concession continued to work undisturbed and some had even thrown rocks at company vehicles. "The miners have come back in even larger numbers than usual," he said.

A spokesman for Glencore, which is based in Switzerland but is London-listed, declined to comment. CLASHES

Some clashes broke out on Monday between miners and police. At least two officers' weapons were seized at one point, Yav and Monga said. One miner and one police officer were injured, Monga said. Union officials and international activists, including Amnesty International, warned that evicting the miners - also known as artisanal miners - by force could lead to violence and rights abuses.

They argue expulsion does nothing to address underlying factors, such as poverty and unemployment, that push people to brave dangerous conditions in mines. "Without an alternative, the artisans won't leave and the army will move in. When soldiers are sent into the field, we all know what happens," said Charles Kumbi, regional programme director with the IndustriALL union.

Army officials could not be reached for comment on Tuesday. Last week's accident, which briefly sent Glencore's shares tumbling 7%, underscored foreign investors' exposure to illegal mining activity on their properties.

Tens of thousands of informal miners operate in and around large industrial mines in Congo. Often equipped with little more than shovels, buckets and straw sacks, they burrow deep underground in search of ore. Accidents are common. Congo produces more than half the world's cobalt, a key component in an electric car and other electronic batteries, but is one of the world's least developed countries, afflicted by corruption, conflict and misgovernment.

Reports about the dire conditions in which some cobalt and copper is mined, including cases of child labour, have piled pressure on producers and end-users to prove supply chains are clean. Companies fear that copper and cobalt will be dubbed "conflict" minerals like gold, tin, tantalum and tungsten, which have been used to finance wars in eastern Congo, said Gregory Mthembu-Salter, former U.N. sanctions monitor in Congo.

"If a lot of people do get killed in this (at KCC), it would be a big step towards that," he said. Numbi said the army evicted thousands of miners from China Molybdenum's nearby Tenke Fungurume mine last week without firing a shot and would act professionally at KCC too.

It was unclear, however, if the miners had abandoned Tenke Fungurume or only retreated to surrounding areas to wait out the operation. Local activists said the area offered to the miners to exploit on another side of the mine has only low-grade ore and is unlikely to satisfy them.