Over 400 school buses and vans were issued 'challans' in Noida and Greater Noida on Thursday for not having adequate safety measures on board the vehicles, officials said.

The action was carried out as part of "Operation Clean", a special initiative of Gautam Buddh Nagar police to make roads safer, the officials said.

The police campaign was carried out on vehicles linked to 129 schools and began at 6.30 am, a spokesperson said.

"During the campaign, 427 school buses and vans were issued 'challans' after they were found not having adequate safety measures and not fulfilling the safety criterion.Another 702 buses and vans were let off with a warning to adopt proper safety measures while having children on board," the spokesperson said.

Around Rs 26,700 was collected in fines during the 11th edition of the "Operation Clean", he said.

Gautam Buddh Nagar Senior Superintendent of Police Vaibhav Krishna said the action was taken after a number of complaints were received about school buses and vans violating traffic rules and compromising the safety of children.

"There have been complaints that these vehicles get overloaded with children, run on wrong lanes, risking lives of children and other commuters. So this campaign was to send out a message that you're being watched when you violate rules. There's no getting away from the law," Krishna told PTI.