MOUNTAINBURG, Ark. (AP) — A tornado ripped through a tiny town in the Ozark Mountains of northwestern Arkansas on Friday, injuring at least four people.

The twister struck Mountainburg, Arkansas, around 4 p.m. Friday as a line of severe thunderstorms rumbled across eastern Oklahoma and western Arkansas.

There were at least three entrapments as the tornado moved through the town of 624 residents about 20 miles northeast of Fort Smith, said Crawford County Emergency Management Director Brad Thomas. At least four people were taken to hospitals, he said, but he didn't know their conditions.

Video from the scene showed uprooted trees, overturned cars, damaged buildings and downed power lines.

Forecasters had expected high winds, large hail and perhaps strong tornadoes across Arkansas on Friday. The Storm Prediction Center said all of the state faced a "moderate risk" of severe weather.

The bad weather was part of a system that brought blizzard conditions to the Northern Plains and high winds that raised the wildfire risk in the Southern Plains.

Forecasters warned that some storms could be intense in Arkansas and adjoining parts of Louisiana, Oklahoma and Texas.