NINE buses that were used to take school pupils to a safari park were taken off the road after police found serious mechanical defects on the vehicles.

The discovery was made during a five-day operation between June 18 and 22 by Central Scotland Police and the Vehicle and Operator Services Agency (Vosa) at Blair Drummond Safari Park, near Stirling.

The most serious defect was an emergency door which could not be secured shut. Officers also discovered braking defects, a faulty exhaust, oil leaks and a broken seat belt.

Sergeant Bob Murphy said: "The buses were checked while pupils were inside the safari park and those with the serious defects were immediately taken off the road.

"The operators then had to find alternative buses to collect the pupils once their visit was over."

He added: "It is extremely worrying that nine buses were so defective they had to be removed from the road with immediate effect.

Speaking about the emergency door, Mr Murphy said: "If somebody had leaned against it they could have fallen out and the consequences do not bear thinking about."

During the operation, 15 drivers were also found to be working in excess of their hours or unable to prove the hours they had worked, and were not allowed to drive until they had had a sufficient rest.

Mr Murphy said: "We want to reassure parents that we will do everything we can, along with Vosa, to make sure their children are travelling on buses that are completely roadworthy.

"We will continue to address this."