Ojiya, Japan ? Yoshikazu Ogawa stood outside the pile of rubble that was once his home, poking around the plaster and wood that had suddenly come crashing down on his two minivans when a series of earthquakes hit northern Japan, killing at least 23 people and injuring some 2,000.

“We’ve got nothing,” he said Sunday, one day after a magnitude 6.8 quake flattened his home and neighborhood in Ojiya, a town of 40,000 about 160 miles northwest of Tokyo. “Our house is destroyed. We have no electricity, no toilet, no telephone.”

Like some 64,000 other people, Ogawa said he and his family planned to spend the night in one of hundreds of makeshift evacuation centers — school gymnasiums, parking lots, even street corners — set up in the region as officials struggle to restore its battered lifelines.

Early today, a 5.6-magnitude aftershock hit the region, jolting survivors huddled in makeshift emergency shelters. It hit near Ojiya, the epicenter of Saturday’s temblor. No damage or injuries were immediately reported.

Prime Minister Junichiro Koizumi pledged that the government would set aside funding for reconstruction. But officials estimated it would take weeks to rebuild roads, bridges and homes and restore essential services.

The quake hit just after sunset Saturday as many people were sitting down to dinner in the scattered towns and rice paddy-ringed villages in Niigata state on the northwestern coast of Japan’s main island.

Several strong quakes followed through the night as a near-total blackout enveloped about 280,000 households, and aftershocks continued jolting the area Sunday.

The Japanese government said 23 people were killed and 1,232 were injured. The dead included five children, the youngest a 2-month-old infant. Public broadcaster NHK reported that some 2,000 people were injured.

The injured overwhelmed local hospitals, where patients were being treated in the hallways. Saturday’s quake also flattened dozens of homes, tore through the pavement of local roads and highways and caused landslides that cut off whole villages.

A series of powerful earthquakes damaged roads, flattened homes and derailed trains Saturday in northern Japan, including this roadway near Ojiya. The quakes killed at least 23 people and injured about 2,000, officials said.

Two trains derailed, but no injuries were reported. One was a bullet train, the first to jump its tracks since Japan began running such trains in 1964.

Military helicopters airlifted stranded villagers from a riverside hamlet, Shiotani, that was cut off when the bridge connecting it to Ojiya was toppled.

“Carrying out rescue efforts is the most important task right now,” said Tsutomu Takebe, secretary-general of the ruling Liberal Democratic Party. “The government is making all the effort to assess the extent of the damage.”

The quake was the most devastating to strike Japan since 1995.