A series of explosions damaged a cottage and two other buildings in this resort community early Monday, sending seven people to hospitals, authorities said. Two people were unaccounted for.

The blasts, about 2:30 a.m., struck a grocery store, a cottage and a maintenance building with a living quarters on the Door County peninsula, which juts into Lake Michigan, said Chief Chris Hecht of the Sister Bay/Liberty Grove Fire Department.

"It was the most unbelievable thing that I have felt in my entire life," said Tamara Little of Milwaukee, who was staying at a nearby resort cabin. "I almost ran into this big shard of glass that was sticking out of the ground."

Hecht did not give details on the two missing people, but Little said a man who had been staying in a cabin next to hers said his brother-in-law and sister could not be found.

The fire chief said the cause of the explosions was not immediately determined. He said most of the buildings in the area use some kind of gas.

"The scene continues to show rising levels of explosive vapor, either propane or some other type of explosive vapor," he said.

Hecht said seven people were taken to Door County Memorial Hospital in Sturgeon Bay and five others refused treatment or sought medical help on their own. He said four of those taken to Sturgeon Bay were later transferred to a Green Bay hospital.

Ellison Bay is about 65 miles northeast of Green Bay. The damaged cottage was part of the Cedar Grove Resort, where Hecht said 49 people were staying.

Jonathan Bastian, a bartender at the Mink River Basin Supper Club in Ellison Bay, said he was finishing up for the night when he heard a succession of explosions, grabbed a portable phone, ran outside and called 911.

"I told them I think half the bleeping town blew up," he said.

Bastian said he saw the Pioneer Store had been toppled as well as the two other building damaged.

The Door County Sheriff's Department closed Highway 42 after the explosions, and Hecht said authorities were urging people to stay away from the scene.