A massive fire damaged or destroyed dozens of wood-frame buildings, mostly unoccupied summer homes, at a 146-year-old Christian center on Easter.

The fire erupted at 4:30 p.m. Sunday, when Christians were celebrating the resurrection of Jesus Christ. But the season hadn't begun yet at the Alton Bay Christian Conference Center on Lake Winnipesaukee, and state Fire Marshal William Degnan said no injuries to civilians had been reported.

"Fortunately, it was at this time of year," he said. "During the summer, it's full."

It was cold and windy Sunday, and Degnan said the strong winds off the lake, the state's biggest, helped spread the flames through the many cottage-style homes at the center, about 30 miles northeast of Concord.

Witnesses said they watched as buildings burned to the ground in minutes.

"As I was looking across the bay, I could see 600 feet of flame lengthwise," John Lobdell told the News 9 television station in Manchester. "The whole entire camp ground looked like it was up in flames."

One firefighter was hurt when a propane tank exploded. Others were treated for smoke inhalation or exhaustion.

The fire was under control by about 8:30 p.m.

The center's Web site says its purpose is to change lives in part by "encouraging commitment to Jesus." It says it tries to accomplish this through evangelism, encouragement of believers and equipping Christians to be effective leaders.

The center, founded in 1863, is on the southeastern corner of the lake. Besides cottages, it features a 70-room motel and a park for recreational vehicles.

The chairman of the center's safety organization, Russell Sample, was with Degnan as crews from numerous surrounding towns worked on the fire, whose cause hadn't been determined.

"A tremendous amount of history has been destroyed," Sample said.