Powerful storms in the US have killed at least 15 people and left a wide trail of destruction across Texas, Oklahoma and Arkansas.

The storms inflicted their worst damage in a region spanning from north of Dallas to the northwest corner of Arkansas, and the system threatened to bring more violent weather to other parts of the Midwest later in the day.

Seven deaths were reported in Cooke County, Texas, near the Oklahoma border, where a tornado Saturday night ploughed through a rural area near a mobile home park, officials said.

The dead included two children, ages 2 and 5, local officials said. Three family members were found dead in one home.

Storms also killed two people and destroyed houses in Oklahoma, where the injured included guests at an outdoor wedding. Tens of thousands of residents were without power across the region.

Up to 50 people sheltered at a truck stop near Valley View. The storm sheared the roof and walls off the building, mangling metal beams and leaving battered cars in the parking lot.

Multiple people were transported to hospitals by ambulance and helicopter in Denton County, Texas, also north of Dallas.

At least five people were killed in Arkansas, including a 26-year-old woman who was found dead outside a destroyed home in Olvey, a small community in Boone County, according to Daniel Bolen of the county’s emergency management office.

Another person died in Benton County, and two more bodies were found in Marion County. In Oklahoma, two people died in Mayes County, east of Tulsa, officials said.

The destruction continued a grim month of deadly severe weather in the nation’s midsection.

Tornadoes in Iowa this week left at least five people dead and dozens injured.

The deadly twisters have spawned during a historically bad season for tornadoes, at a time when climate change contributes to the severity of storms around the world. April had the second-highest number of tornadoes on record in the country.

Meteorologists and authorities had issued urgent warnings to seek cover as the storms marched across the region late Saturday and into Sunday morning.

Daybreak began to reveal the full scope of the devastation.

In Valley View, near the truck stop, the storms ripped the roofs off homes and blew out windows.

Clothing, insulation, bits of plastic and other pieces of debris were wrapped around miles of barbed wire fence line surrounding grazing land in the rural area.

The severe weather knocked out power for hundreds of thousands of homes and businesses in the path of the storms.

The system causing the latest severe weather was expected to move east over the rest of the holiday weekend.

The start of the Indianapolis 500 was delayed as a strong storm pushed into the area, forcing Indianapolis Motor Speedway officials to evacuate about 125,000 race fans.

The video boards inside the speedway flashed that a severe thunderstorm warning was in effect as the band of rain, along with dangerous wind and lightning, approached from the west.

More severe storms were predicted in Illinois, Missouri and Kentucky.

The risk of severe weather moves into North Carolina and Virginia on Monday, forecasters said.