A NINE-year-old boy suffered a serious head injury after he fell through the roof of a factory in Blackburn.

An investigation is underway after Leon Langford was discovered at the premises of North West Tippers, in Rockfield Street, early on Monday morning.

He had been reported missing on Sunday night by his step-mum Adele and dad Dave Langford, after he was last seen playing with friends at the nearby Ivy Street playground, around 4pm.

Workers at the site are understood to have found the boy, earlier yesterday, as they arrived for work.

Paramedics from North West Ambulance Service, which sent a rapid response vehicle and an ambulance to the area, stabilised the boy.

He was then airlifted to Alder Hey Children Hospital with a head injury and is believed to have been placed in an induced coma.

Several police and fire service vehicles remained at the scene, which was sealed off between Highfield Road and Hall Street junctions, throughout yesterday.

A drone was dispatched by police and fire service investigators, to survey the factory while officers inspected the roof from the Highfield Road end of the factory.

A police spokesman said the boy was in a serious condition with a suspected head injury.

His father, Dave Langford, has paid tribute to those who took the time to help with the search for his son on Sunday night and early Monday morning.

He posted on Facebook: "Really want to say massive thank you to all that helped me through the night and this morning to help find my son.

"He is in a bad way but on the way to Alder Hey."

The boy’s aunt, Cheryl Baxter, added: "He's fallen through a roof and got bad injuries. They've had to put him to sleep and fly him to another hospital."

And his uncle, Lee Langford, said: "My thoughts go out to my brother, Dave Langford, and all the family. Hope Leon makes a speedy recovery."

Another family member, Donna Bell, said: "Thinking of my cousin's little boy. Hope he's guna be okay."

The Health and Safety Executive has also been notified about the incident.

Staff from the company, which has manufactured commercial tipping vehicles since 1974, refused to comment yesterday.

A North West Ambulance Service spokesman said that they were alerted to the incident at around 8am and confirmed that the patient had "serious injuries".

Two air ambulances were initially dispatched to the scene, said the spokesman, but one was later stood down.

A Lancashire Fire and Rescue Service spokesman said specialist officers were in attendance to assist their police colleagues in securing aerial views of the premises, via their drone device.

A spokesman for the North West Air Ambulance charity said a helicopter landed nearby to deal with the casualty.