A "worrying" number of vehicles taking children to and from school are unsafe, according to police.

Defects were found on 72 per cent of vehicles checked in a two-week campaign by Dewsbury Road Traffic Department, which includes the Spen Valley, with 38 per cent receiving a prohibition notice.

Police stopped 39 taxis, coaches and mini-buses as part of the national Operation Coachman campaign, which ended on Friday.

Vehicles were checked at seven local schools picked at random including Howden Clough Girls High School in Birstall, Hartshead Moor School in Cleckheaton and Fairfield School in Heckmondwike.

Of the three taxis checked, one received an immediate prohibition notice, taking it off the road, because of faults found its tyres, steering and exhaust. It was also issued with a defect note.

Of the six minibuses stopped, three received immediate prohibition notices, for defective tyres, brake lights or the dangerous condition of the vehicle. Three defect notes were also issued, for the condition of the lights, condition of the vehicle and seat belts. Of the six stopped, only one was free from any defect.

Of the 30 coaches stopped, seven received immediate prohibition notices and four received delayed prohibition notices. The delayed notices give owners a number of days to remedy the defects or face having them taken off the road.

Thirteen of the vehicles were served with defect notes and only 11 of all the coaches were free from any defects.

Jackie Eames, headteacher at Howden Clough Girls High School, said: "I'm rather alarmed by these statistics because I do have girls who are travelling from other areas by minibus. Safety should always come before cost and I'm glad the police are doing these checks. These figures don't entirely surprise me because there are cowboys out there."

Ian MacDonald, headteacher at Hartshead Moor School, said: "There does need to be some systematic spot checks by the police on the buses to ensure that their vehicles are always roadworthy."

Sergeant Alan Kaye, Dewsbury's divisional road traffic commander said: "We didn't expect such a high number of defects because we expect people who operate such facilities to take responsibility and ensure vehicles are roadworthy.

"This is worrying especially as these vehicles are taking children to school. Hopefully the initiative will have made those responsible more aware of their full responsibilities and they will take some action to rectify this."

Although the operation had ended, he said his department would continue to monitor such vehicles on a regular basis