Emergency services are at the scene of a Knebworth building site after a wall collapsed onto a man’s leg this morning.

The Comet: Emergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOOEmergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOO (Image: ©2018 Archant)

Police were called at 8.58am by the ambulance service to the former Chas Lowe and Sons Builders’ Merchants site in London Road, where an external wall had collapsed onto a man’s leg.

The fire service were also called shortly after police to assist with a casualty, who was said to be injured but not trapped.

The ambulance service said the man was taken to Lister Hospital in Stevenage with serious leg injuries.

Building control are now in attendance and awaiting arrival of a structural engineer, with police closing London Road between Watton Road and St Martin’s Road.

The Comet: Emergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOOEmergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOO (Image: ©2018 Archant)

The ambulance service said the man was taken to Lister Hospital in Stevenage with serious leg injuries.

The site is being turned into a retirement living development by housebuilder McCarthy and Stone, and is being named Lowe House in honour of Charles Lowe – owner of Chas Lowe and Sons Builders’ Merchants.

The family firm had been based at the London Road site for decades prior to a decision to cease trading last year.

The assets of the business were sold to builders’ merchants Gibbs & Dandy, which opened a branch on Gunnels Wood Park in Stevenage last summer.

The Comet: Emergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOOEmergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOO (Image: ©2018 Archant)

The Comet: Emergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOOEmergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOO (Image: ©2018 Archant)

The Comet: Emergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOOEmergency services at the scene of an accident on the McCarthy and Stone building site in London Road, Knebworth. Picture: DANNY LOO (Image: ©2018 Archant)