Moscow ? The people of Kyrgyzstan voted Sunday to adopt a new constitution in a referendum that appeared to proceed calmly despite smoldering tensions after ethnic clashes left hundreds dead two weeks ago.

By holding the vote without violence — and winning 90 percent support for its proposals — the country’s fragile provisional government can claim a popular mandate that may boost its authority and help it to take greater control of regions still loyal to Kurmanbek Bakiyev, the recently ousted president.

“This is no longer an interim government but a legitimate government,” said Roza Otunbayeva, the leader of the opposition coalition that seized power in a bloody revolt in April. “We are proud of our people. We are proud of our country, which made this choice at a difficult hour.”

Speaking to reporters in the capital, Bishkek, after traveling to the riot-torn city of Osh to cast her ballot, Otunbayeva said the public had voted overwhelmingly to establish Central Asia’s first parliamentary democracy, to schedule elections for October and to let her serve as acting president until the end of next year.

Election officials said that more than two-thirds of eligible voters went to the polls under tight security — a remarkable turnout given the recent clashes in the country’s south between ethnic Kyrgyz and minority Uzbeks, in which about 400,000 people were driven from their homes and as many as 2,000 were killed.