People living in Sparrows Herne, Bushey, were woken up to sounds of siren and the smell of smoke at around 6am on Tuesday (April 6).

Hertfordshire Fire and Rescue issued a warning of a "large attendance" of emergency services at the scene to tackle the fire.

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One eyewitness, Lisa Lorton, said after being woken up by the noise, she looked outside and saw smoke.

"It’s quite a bad fire, I think two houses are gone", she said.

A police cordon at the scene (Photo: Lisa Lorton)

Another person who lives opposite to the homes, Grace Simmons, said the two houses affected had "severe damage".

Two houses had "severe" damage (Photo: Nathan Louis)

Fire services across Hertfordshire – including a crew Hertford -– were called to the scene.

A police cordon at the scene (Photo: Grace Simmons)

And hours later, cordons remain place in Sparrows Herne from Larkin Drive up until Elstree Road.

A police cordon at the scene (Photo: Nathan Louis)

The Observer has been told there are no injuries, but a crime scene is in place as emergency services work to determine how the fire started.

A fire investigation dog unit is on scene and some firefighters remain on site investigating the affected homes.

It is understood that wind caused the fire to spread from one house to another.

Images show significant damage both at the front of and back of buildings, although it is unclear if it the same house.

Hertfordshire Fire and Rescue were contacted for further information.