CONAKRY, Guinea (AP) - A United Nations human rights official says a three-member U.N. commission has arrived in this West African nation to investigate the September massacre in which troops fatally shot pro-democracy demonstrators and raped women in broad daylight.

Sonia Muller-Rappard said the all-African commission arrived in Conakry on Wednesday. The group was appointed by U.N. Secretary-General Ban Ki-moon last month to determine who was responsible for the massacre.

A peaceful pro-democracy rally in the West African country on Sept. 28 took a violent turn when presidential guard troops opened fire on tens of thousands of demonstrators. A Guinean human rights group says 157 people were killed. The government put the death toll at 57.

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