By JACK DURA

BISMARCK, N.D. (AP) — Two tornadoes that killed six people in North Dakota and New York each had wind speeds topping 100 mph and caused brief but widespread damage as they tore through largely rural areas, officials said.

Three people, all in their 70s and 80s, died in rural Enderlin, North Dakota, during a storm that struck late Friday and early Saturday, the Cass County Sheriff’s Office said. Three others, including twin 6-year-old sisters, died Sunday in a storm that struck the hamlet of Clark Mills in central New York, the Oneida County Sheriff’s Office said.

The National Weather Service gave preliminary ratings of EF-2 to EF-3 or potentially higher for three tornadoes that struck eastern North Dakota — meaning wind speeds of 111 to 135 mph and 136 to 165 mph, respectively, with varying severity of damage. EF-3 and stronger ranges are not usual for the Northern Plains, National Weather Service Meteorologist Jacob Spender said.

“As we go higher on the scale, it’s not as common but they can still happen,” he said.

The tornadoes uprooted numerous trees, tossed train cars and damaged houses, Spender said.

The night included supercells in southeastern North Dakota and a derecho — a powerful windstorm — that tore across the state to the east.

The wind lashed little Page, North Dakota, population 250, for over an hour, ravaging trees, roofs and structures, Mayor Jim Heidorn said. Half the town’s trees are gone, he said. Cleanup might stretch throughout the summer.

Kylie Weber was hunkering down with her family and some friends at her family’s rural home near Oriska when the storm sucked her bedroom window out of the wall, blew the room’s door off its hinges and ripped off part of the roof, she said. Their farm also lost a grain bin, among other damage.

Thousands of people were still without power Monday.

Having numerous ways to be alerted to severe weather is crucial, such as by smartphone and radio, Spender said. Many people vacation at lakes in remote areas in summer, and nighttime storms can be especially dangerous because people can’t see what’s coming, he said.

The Weather Service confirmed that a tornado packing 105 mph winds touched down in upstate New York before dawn Sunday during severe thunderstorms. The tornado was blamed for the deaths of three people.

The EF-1 tornado was on the ground for more than 2 miles and was about 300 yards wide at its peak as it spun from Clark Mills to North Clinton in Oneida County, west of Utica, the Weather Service said.

Trees fell on three homes, killing twin 6-year-old girls in one and a person in another, officials and the Weather Service said. The twister also destroyed a historic grist mill along Oriskany Creek. The Weather Service said the thunderstorms also produced high winds that caused other scattered damage.

Associated Press reporter Dave Collins contributed from Hartford, Connecticut.