Oklahoma/Missouri:
The ferocious power of one of the devastating tornadoes that struck the US state of Oklahoma on Tuesday was captured on camera by storm chasers, who followed the twister as it left a trail of devastation in its wake.
The tornado is seen churning through the Chickasha area, 25 miles (40 kilometers) southwest of Oklahoma City.
Officials said a 26-year-old woman died when the twister hit a mobile home park where residents had been asked to leave.
A dozen people were injured and hundreds were displaced in the area, they added.
That twister was just one of the many tornadoes that struck Oklahoma and also the states of Arkansas and Kansas on Tuesday, killing at least 15 people.
Those powerful storms came two days after the nation's deadliest single tornado since 1950 killed at least 125 people on Sunday in Joplin in southwest Missouri.
Survivors of that tornado were on Wednesday continuing to salvage what was left of their homes, hoping to find treasured possessions amongst the debris.
Joplin resident Anita Stokes said it was a miracle she survived when the tornado roared through the town.
"My son pushed me in the bathroom hallway and lay on top of me, and then I heard the windows busting and a lot of the wind just moving us back and forth."
Others continued the search for missing loved ones, many using social networks as a tool.
Several online efforts have focused on Will Norton, a Joplin teenager who vanished on his way home from his high school graduation ceremony.
Norton was driving with his father, Mark Norton, when the storm hit their vehicle, which flipped several times, and Will was thrown from it.
Mark Norton tried to grab his son, but the storm was too strong. He was taken to hospital on Tuesday, seriously hurt, but still able to talk to his family about what happened.
More than 19,000 people supported the "Help Find Will Norton" community page on Facebook, and Twitter users were tweeting heavily about the missing youth.
Tracey Presslor, Will Norton's aunt, said she was grateful for all the messages on Facebook.
"I read it at night when I have time, I just cry because I can't believe all these people are praying which we're so grateful for Will and everybody else, I feel like I love all these people, like they're part of our family, and it's really heart breaking and heartwarming at the same time."
There has been no official confirmation of the number of missing, and authorities have cautioned that people who are unaccounted for are not necessarily dead or trapped in debris.
Many, if not most, of them probably survived the storm but failed to tell friends and family where they were, they suggested.
It's left relatives and friends with a small ray of hope that their loved ones might still be alive.
Elsewhere in Missouri, as many as 25 people suffered minor injuries on Wednesday when a tornado damaged several homes and businesses in the central city of Sedalia, 75 miles (120 kilometers) east of Kansas City.
Officials in Sedalia ended the school year several days early because of damage to buses. In one hard-hit neighbourhood, law officers stood on corners and electrical crews worked on power lines as people cleaned debris and sifted through belongings.
Further tornadoes in the area have not been ruled out. Heavy rain and strong winds have been forecasted for most of midwest United States and the weather service has placed most of the states in the area under a tornado watch.