A woman died and 10 people were injured in an early morning crash on the M5 in Somerset.
Elaina Beard, 29, from Bridgwater, is believed to have got out of a car involved in the four-vehicle smash on the northbound carriageway at about 06:20 GMT.
She was hit by several vehicles on the opposite carriageway, police said.
Her family issued a statement saying they were "totally heartbroken" by her death.
Avon and Somerset Police said formal identification of the victim was yet to take place, but they believed the woman who was killed to be Ms Beard.
Her family described her as "a loving sister, daughter, auntie and friend, who was so caring both as a carer in her day job and a family member."
Ms Beard worked for Bluebird Care. The company's chief operating officer, Duncan Berry, paid tribute to her.
"It is evident from the comments made by those she worked with that Elaina was a hugely valued and liked member of her team," he said.
Insp Darren Jarvis from Avon and Somerset Police said: "Unfortunately one of the drivers has been struck by other vehicles driving on the southbound carriageway.
"Not all of those vehicles have been identified at the moment.
"I would ask that anybody that was travelling on that road at that time, and may not have realised what happened and what they may been involved in, I would ask them to come forward."
Three people had to be cut free from vehicles, Devon and Somerset Fire and Rescue Service said.
About 15 crews were deployed by South Western Ambulance Service including rapid response vehicles and two air ambulances.
The road was closed for most of the day between Taunton and Wellington.
"We treated 10 patients in total, with eight being taken into hospital," the ambulance service said.
"Six patients were taken to Musgrove Park Hospital in Taunton by road ambulance and two were taken to Southmead Hospital in Bristol by air ambulance."