FOOTAGE has been shared online of pupils coughing in a smoke-filled school bus.

Youngsters from Our Lady's High School in Cumbernauld are seen using their clothes to cover their mouths as the smoke swirls round them.

Monday's footage shows the McNairn's coach seem to fill with black smoke as youngster cough.

It is the second McNairn's incident and comes after a coach travelling to St Ambrose High in Coatbridge filled with high levels of carbon monoxide.

A concerned mother posted on the Safety 1st On NLC School Buses Facebook page: "Our Lady’s High School Cumbernauld 16/4/18 McNairn’s coaches.

"This is how bus company transports our kids.

"Bus engine fumes/smoke belting inside of bus, driver response open the door while driving from school to Stepps while kids standing getting choked with fumes.

"Via the motorway.

"When it’s fatal I’m sure North Lanarkshire Council will listen or maybe when it’s their child."

Coatbridge families organised a boycott of the buses last year in the hope something would be done.

A spokesman for North Lanarkshire Council said: “The safety of all our pupils is of paramount importance.

"SPT manage all school transport contracts on behalf of the council and a meeting took place today between them and the bus provider to discuss the incident which took place on Monday, April 16.

“A replacement bus has been provided.”