(CNN) -- A former speaker of the Rwandan parliament warned that his country could again descend into chaos and violence, 15 years after the genocide that killed as many as 1 million people.
Joseph Sebarenzi, who lost most of his family in the massacres, told CNN's Christiane Amanpour on Wednesday that frustration is growing in Rwanda at what he called President Paul Kagame's concentration of power. He warned that frustration could spill over into violence if not addressed.
Rwanda will hold a presidential election next August, its second since the 1994 genocide. Kagame, who's credited with turning Rwanda into a model of economic development, is expected easily to win the election.
But Sebarenzi, who wrote a heartrending account of the genocide called "God Sleeps in Rwanda," said the nation continues to face acute problems over what he believes is the failure of the Hutu and Tutsi tribal communities in the country to reconcile properly. Most of the massacre victims were Tutsis killed by Hutus. "People need to reconcile individual to individual, but also community to community," Sebarenzi said.
He said the reason Rwanda had a genocide was that the then-president -- Juvenal Habyarimana, whose plane was shot down hours before the nation descended into chaos -- had too much power. Sebarenzi accused Kagame of now amassing too much power in the presidency and failing to create strong institutions that could check his authority.
"Instead of having a president that is too powerful, (Rwanda) should have a powerful parliament, judiciary, and a civil society", he said.
Author Philip Gourevitch, who wrote a prize-winning account of the massacres, "We Wish To Inform You That Tomorrow We Will be Killed With Our Families," offered a more optimistic assessment.
He said that if Kagame wins another seven-year term, 2017 will show whether Kagame will live up to his promise to become the first retired civilian leader in Rwanda history.
Gourevitch credited Kagame with remarkable achievements in Rwanda. He said the country has made more progress than anyone could have imagined 15 years ago. "We're talking about the building of a state from total destruction, from something considerably worse than zero."
Rwanda's future lies with the country's younger generation, which will refuse to inherit the world that the older generation will leave behind, Gourevitch said.
"You're starting to hear people speak up and that's a big change," he said.