It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Police Reassurance Over 'Abductions'
Police are trying to reassure parents in Gillingham following two incidents in recent weeks involving children in the area.
Officers were called following reports of suspicious incidents in Gillingham area on Tuesday 17 July 2012 in the town area and on the 27 July in the Ham area.
Both cases reported that men had approached and spoken to a child. Enquiries were made and police say no offences have been disclosed.
Gillingham Sergeant Mark Creasey, said:
"I really want to stress that these incidents were not abductions. While the children were approached and spoken to, no physical contact was made.
"However, these are unusual incidents and we are keen to trace the men involved.
"The Force is aware of rumours that are circulating on social network sites.
"We would advise parents that there is no specific cause for concern at this time and we would ask that members of the public to steer clear of the rumours and do not circulate them further.
"I would like to reassure the public that officers are on patrol in the area. Both children did the right thing by telling their parents on this
Witnesses and anyone with information should call Dorset Police in confidence on 101.
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