It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Hampshire Boy Dies In US Shooting
A Hampshire-born boy is one of the victims of the worst school shooting in America's history.
Dylan Hockley, 6, was shot dead by a gunman at an elementary school in Connecticut.
He was born in Hampshire to a British father and American mother.
Twenty children and seven adults, including the gunman's mother, died before Adam Lanza, 20, turned a gun on himself at the Sandy Hook Elementary School in Newtown.
It has been confirmed that US President Barack Obama will attend a memorial service in Newtown later today, and will speak at an interfaith vigil for families of the victims.
Meanwhile, a father has paid an emotional tribute to his murdered six-year-old daughter, after police released the names of the gunman's 27 victims.
Robbie Parker said his final conversation with Emilie was in Portuguese, the language he was helping to teach her.
"She told me 'good morning' and asked how I was doing, and I said that I was doing well," he told reporters.
"She said that she loved me, and I gave her a kiss and I was out the door."
Headteacher Dawn Hochsprung and school psychologist Mary Sherlach both died as they tried to confront the gunman.
The pair were in a meeting with therapist Diane Day on Friday, when the gunman began shooting at 9.30am.
On hearing the shots, they both jumped out of their seats and ran out of the room.
"They didn't think twice about confronting or seeing what was going on," Ms Day said.
Ms Hochsprung is also believed to have switched on a loudspeaker system in the school to alert students and staff to the danger.
"She was just an amazing woman ... the kids loved her. It's a huge loss for our school and our town," said assistant librarian Maryanne Jacobs.
Fourth-grade teacher Theodore Varga said: "You could hear the hysteria that was going on.
"Whoever did that saved a lot of people. Everyone in the school was listening to the terror that was transpiring."
Another hero was said to be first-grade teacher Vicki Leigh Soto, 27, described by police as someone who "put herself between the kids and the gunman's bullets".
Her body was found huddled with the students in a classroom closet, according to The Wall Street Journal.
Youth soccer coach David Flook, originally from Northampton, England, told Sky News of the turmoil his town is now in.
"Everybody is absolutely devastated. People don't know what they can do," he said.
He described Newtown as the "least dangerous place on earth".
He added: "It was the perfect town."
The father of gunman Adam Lanza released a statement on Saturday night. He said: "Our hearts go out to the families and friends who lost loved ones and to all those who were injured.
"We are in a state of disbelief and trying to find whatever answers we can. We too are asking why."
Violent crime was up 37% in the last year. Police say it's mainly due to a change in how offences are recorded.
Anne-Marie Ellement took her own life after claiming she'd been raped by two colleagues.
48 Zany Zebras sculptures were sold off to raise money for Marwell Zoo.
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