After two days of deadly clashes, Guineans will vote on Sunday in their country's second presidential election since the end of military dictatorship in 2009.
The vote is seen as a key test of the impoverished West African nation's transition to democracy following decades of strongman rule.
Pitched battles broke out on Thursday and continued throughout Friday after President Alpha Conde refused an opposition demand to postpone the election, which critics say is rigged heavily in his favour.
Conde is widely tipped to win a second term in office, beating his main challenger Cellou Dalein Diallo and six other presidential hopefuls. But opposition parties have announced they will not accept the results while alleging widespread voting irregularities.
Youths from both sides of the political divide hurled rocks at each other in several parts of the capital Conakry leaving two dead and many wounded, according to police. Another five people were killed elsewhere in the country on Thursday.
In Conakry's market neighbourhood of Madina, rioters looted shops and set fire to property as police and soldiers fired tear gas to disperse the rampaging crowd.