* Government ordered miners out after deadly landslide
* About 2,000 miners operate illegally at southeastern site
* Some clashes with police as eviction set to begin
By Fiston Mahamba and Aaron Ross
GOMA, Democratic Republic of Congo, July 2 (Reuters) - I llegal 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 subsidiary of Glencore, 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 on the ground and an operation to clear the estimated 2,000 miners in the would begin on Tuesday.
Reached by telephone, Joseph Yav, chief of staff to the provincial governor, said police had begun a process of voluntary closures of 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 miners inside the concession continued to work undisturbed, adding that some had 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 also has offices and is listed in London, declined to comment.
Some clashes broke out on Monday between miners and police encouraging them to leave, with at least two officers' weapons seized at one point, Yav and Monga said. One miner and one police officer were reported injured, Monga said.
Local and international activists have warned evicting the miners by force could lead to violence and rights abuses.
They say expulsion does nothing to address underlying factors, such as poverty and unemployment, that push people to brave dangerous conditions in mines.
"These artisanal miners merely try to eke out a living and sending in the army against them would be completely irresponsible," Sarah Jackson, a regional official for Amnesty International, said in a statement.
Army officials could not be reached for comment on Tuesday.
Last week's accident, which briefly sent Glencore's shares tumbling 7%, underscored the risks to foreign investors from 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 dozens of metres below ground in search of ore. Accidents are common.
Numbi said the army evicted thousands of miners from China Molybdenum's nearby Tenke Fungurume mine last week without firing a shot.
It was unclear, however, if the miners had abandoned that site or only retreated to surrounding areas until the operation was over. Local activists said the area offered to the miners to exploit on another side of Tenke Fungurume has only low-grade ore and is unlikely to satisfy them.
Despite boasting rich reserves of copper, cobalt, gold, diamonds and tin, Congo is one of the world's least developed countries, afflicted by corruption, conflict and misgovernment. (Additional reporting by Joe Bavier; Writing by Aaron Ross; Editing by Andrew Cawthorne)