Greece’s Prime Minister Concedes Election Defeat, Government Official Says

ATHENS — Greek voters appear to have turned out their leftist prime minister in elections that came after a decade of grueling economic austerity, casting their lot with a resurgent center-right New Democracy party.

Prime minister Alexis Tsipras called his opponent, Kyriakos Mitsotakis, a Harvard-educated former banker and son of a former Greek prime minister, to concede defeat, a spokesman for New Democracy said. A government official confirmed the call.

Initial results showed that Mr. Tsipras’s Syriza party, which has ruled Greece for the past four years, had suffered a major defeat at the hands of New Democracy.