CONA KRY (Reuters) - At least two people were killed when Guinea security forces wielding truncheons and tear gas grenades cracked down on an opposition protest in the capital on Tuesday, hospital sources said. Tensions are rising in the West African state ahead of a parliamentary election that the opposition says is being rigged in advance by President Alpha Conde. A doctor at Conakrys Donka Hospital told Reuters on condition of anonymity that the hospital had received two corpses one apparently stabbed to death and the other apparently beaten to death. Leading opposition figure Cellou Dalein Diallo, who had organized the rally, said three people had been killed and that security forces had used live rounds.