A powerful storm system rumbled through the central and southern United States on Sunday, spawning a massive tornado that killed at least eight people in central Arkansas and another that killed someone in Oklahoma.

The Arkansas tornado touched down about 10 miles west of Little Rock at around 7 p.m. and moved northeastward for at least 30 miles, the National Weather Service reported. It missed the state capital but passed through or near several of its suburbs, causing widespread damage in the communities of Mayflower and Vilonia.

Matt DeCample, a spokesman for Gov. Mike Beebe, said the tornado killed four people in Faulkner County, three people in Pulaski County and one person in White County.

The tornado, which grew to be a half-mile wide, turned buildings into rubble and stripped the leaves and smaller branches off of trees.

It was one of several tornadoes that touched down Sunday as a large storm system moved through parts of the Plains, Midwest and South.

Less than two hours before the Arkansas tornado struck, a twister hit the small northeastern Oklahoma community of Quapaw, killing one person and injuring six others, Ottawa County sheriff's dispatcher Kelli Soechs said. Earlier Sunday, another Ottawa County sheriff's dispatcher reported that two people were killed. Soechs declined to explain the discrepancy.

Five of the six injured in Quapaw were treated and released from Baptist Regional Health Center in Miami, Okla., said hospital spokeswoman Kristie Wallace. The sixth, who was in fair condition with a broken bone, was kept overnight, she said.

Ottawa County Emergency Management director Joe Dan Morgan said Quapaw, which has about 900 residents, was heavily damaged by the tornado.

"Looks like about half of town got extensive damage as well as the fire department," Morgan said.

After hitting Quapaw, the tornado moved northward into Kansas and struck Baxter Springs, a city of about 4,200 residents about 5 miles away. Cherokee County, Kan., sheriff's dispatcher Josh Harvey said the tornado that hit Baxter Springs injured several people and caused extensive damage, but that no deaths had been reported. He said first responders were going from house to house checking on residents' wellbeing.

Tornadoes also touched down Sunday in Nebraska, Iowa and Missouri. Tornado warnings, which indicate the greatest threat of a strike, were also in effect for parts of southeastern Missouri and northeastern Arkansas as of 9 p.m. CDT.

One of Sunday's twisters touched down northwest of Joplin, Mo., where a massive tornado in May 2011 killed 161 people, injured many others and leveled a large swath of the city. Sunday's twister didn't hit Joplin.

The first reported tornado Sunday touched down in a rural area in central in Nebraska. The weather service said it remained on the ground for only a short time, and there were no immediate reports of damage.

Forecasters warned that areas that weren't hit by tornadoes were still at risk of damage from hail and powerful straight-line winds. Forecasters warned of hail stones as big as baseballs and wind gusts that could reach hurricane-force - 75 mph or higher.

Gusts of up to 60 mph were registered during a storm that hit southeastern Iowa on Sunday that damaged several buildings, including a barn that injured someone when it was blown over.

Earlier Sunday afternoon, a strong line of storms moved through west-central Missouri, bringing winds that reached 70 mph hour near Chillicothe, Mo., that toppled some trees.

The Missouri Highway Patrol also reported a tractor-trailer was blown onto its side on Interstate 70 about 30 miles east of Kansas City about 1 p.m. No one was injured. The weather service received a report from Plattsburg, Mo., where an anemometer measured 58 mph before it blew away. Golf ball-sized hail was reported at Overland Park, Kan., and Trimble, Mo.

Severe thunderstorm watches covered portions of Iowa, Illinois and Missouri through Sunday night. The primary threats were damaging wind gusts and large hail.

To the southeast, northern Louisiana and Mississippi were bracing for severe storms along with the possibility of flash flooding. The predictions prompted Barksdale Air Force Base near Bossier City, La., to cancel its air show on Sunday. The National Weather Service said northern Alabama could see rain and flash flooding, while central and northern Georgia could see storms and heavy rain.

Sunday was the third anniversary of a 122-tornado day, which struck parts of Mississippi, Alabama, Tennessee, Virginia and Georgia and killed 316 people.

Meanwhile, runners in Oklahoma City took shelter early Sunday as hail and high winds delayed the Oklahoma City Memorial Marathon by 105 minutes to let a severe thunderstorm pass through.