State television aired pictures of scattered debris
At least 87 people have been killed after troops in Guinea opened fire on a huge opposition rally in the capital Conakry, reports say.
An earlier death toll of 58 rose by nearly 30 late on Monday, according to unnamed police sources.
Some 50,000 people rallied against Capt Moussa Dadis Camara who seized power in Guinea in a bloodless coup last year.
The rally was triggered by indications he is to reverse a pledge not to run in a presidential vote set for January.
They just started to shoot people directly... They tried to kill us
Opposition leader Sidya Toure
"There are 87 bodies that were collected in and around the stadium after the military came through," a police source told the AFP news agency.
Four women are among the dead.
There has been no independent confirmation of the casualty figures, and the Guinean authorities have made no public comment.
Meanwhile, France issued a statement strongly condemning the "violent repression" of opposition demonstrators in its former colony.
The BBC's Alhassan Sillah says a doctor at government hospital in Conakry said his wards looked like "a butchery".
Reports also say at least two opposition leaders have been arrested.
Captain Moussa Dadis Camara (L) may stand for president
"They just started to shoot people directly... They tried to kill us," Sidya Toure, former prime minister and now an opposition leader, told the BBC's Focus on Africa from a hospital.
He said he had been badly injured in the head, and was speaking secretly from the hospital's toilet as the military was not allowing opposition members any contacts with the media.
Our correspondent says the demonstrators later dispersed, but the military is out in force mounting checkpoints on many roads.
Driving through the capital, our correspondent says he saw burnt-out vehicles around the roads and a burnt-out police station.
The atmosphere was "very strange and fearful", with very few cars on the road, our correspondent adds.
Capt Camara staged a coup hours after the death of President Lansana Conte, who had ruled for more than two decades.
The military takeover initially had some popular support, but in recent weeks there have been several anti-government protests.
This is only the beginning of demonstrations and counter-demonstrations we can expect in the next few months
Guinea expert Gilles Yabi
They appear to have been sparked by hints from Capt Camara that he may stand for president in January.
In Conakry, demonstrators gathered outside the capital's largest stadium, carrying placards reading "No to Dadis" and "Down with the army in power", according to the AFP news agency.
But the demonstration had already been banned and the stadium was closed and guarded by large numbers of police.
Clashes between police and demonstrators followed, with officers charging the crowds and firing live ammunition.
Guinea expert Gilles Yabi told the BBC's Focus on Africa programme that the rally was not a surprise.
"This is only the beginning of demonstrations and counter-demonstrations we can expect in the next few months," he said.
Should Capt Camara stand for president, he said, it would be a violation of the tacit agreement between military and civil forces which has kept him in power.
And it would mark a perpetuation of the kind of rule that Guinea has seen for the past decade - which the military had promised to sweep away.
Capt Camara's rule has been characterised by eccentric displays of power - such as forcing members of the elite presidential guard to beg for forgiveness on national TV after they roughed up a veteran officer.
Former aides and officials have been accused of corruption and links to the drugs trade, including the son of former President Lansana Conte, who was shown confessing on TV to smuggling cocaine.
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