* Death toll seen rising as more bodies counted
* Crackdown condemned, AU warns of sanctions
CONAKRY, Sept 29 (Reuters) - The African Union threatened Guinea's military junta with sanctions on Tuesday as the death toll climbed from a crackdown by security on opponents of military ruler Captain Moussa Dadis Camara.
The toll from Monday's violence climbed as eyewitnesses counted dozens more corpses on top of at least 58 bodies seen in a hospital in the capital Conakry after soldiers fired live rounds at protesters to halt a rally at a local stadium.
The clashes in the world's top bauxite exporting country were the worst since Camara seized power in a 2008 coup and followed months of wrangling between Camara and his rivals.
The African Union called on Camara to confirm he would honour a pledge not to stand in a presidential election due in January and so allow transition to civilian rule.
"In this respect the (AU) Commission is preparing a report on the developments in Guinea and possible measures to be taken, including sanctions," it said in a statement which did not elaborate what steps could be envisaged.
U.N. Secretary-General Ban Ki-moon, and former colonial power France condemned the killings, which eyewitnesses said were unprovoked and indiscriminate.
"Soldiers were firing at people and those who tried to get out (of the stadium) were caught and finished off with bayonets," Guinean human rights activist Souleymane Bah told Reuters of the clashes in the sports stadium.
Bah said he had seen dozens of lifeless bodies in the stadium after soldiers dispersed the crowd, and confirmed widespread reports of abuses by soldiers.
"I saw soldiers strip women naked, spread their legs and stamp on their privates with their boots," he said by telephone.
Camara has yet to make a formal announcement on whether he will stand for the election, but diplomats have said he has spoken in private of his plans to be candidate.
Cellou Dalein Diallo, leader of major opposition group the Union of Democratic Forces of Guinea (UFDG), and several other politicians were arrested by the security forces.
Camara seized power after President Lansana Conte died in December 2008. He enjoyed initial support from a population hungry for change after decades of Conte's rule left the mineral-rich nation in disarray.
However, increasingly erratic behaviour, including crackdowns on former backers in the military, attacks on mining companies the country is so dependent on and the likelihood he will stand in a poll due in 2010, have fuelled instability.
Mining firms like UC RUSAL and Rio Tinto
have not indicated they are ready to leave Guinea despite a series of disputes, but officials say government revenues from mineral exports will fall dramatically next year, putting the budget under strain [ID:nLS236707]. (Writing by Mark John; Editing by Giles Elgood)
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