Watford residents have been warned to keep windows shut and avoid Hagden Lane following a "serious" fire this morning.

Emergency services were seen rushing to the blaze at a commercial property at around 6.30am.

Latest update: More details emerge after fire rips through Watford business 

Herts Fire and Rescue Service posted on X, formerly Twitter: "We currently have multiple crews dealing with a building fire at a commercial property in Hagden Lane, Watford.

"Please avoid the area and if you live locally keep your windows and doors shut."

Herts Police said they were at the scene of "an industrial fire on Hagden Lane", adding road closures were also in place in Vicarage Road, Euston Avenue and some surrounding streets. They also urged people to avoid the area.

An onlooker reported seeing the police and fire service at the scene, saying it "looks serious" shortly before 7am.

As of 11am, it is understood Herts Police had left the scene but the fire service were still investigating.

A force spokesperson told the Watford Observer: “Police were contacted just after 5.50am today (26 November), to report a fire at a unit on Hagden Lane in Watford. Officers assisted the fire service with local road closures. No arrests were made and no injuries reported. All road closures have since been lifted.”

There appears to be slight delays in the area around Hagden Lane and Watford General Hospital, according to Google Maps.

There is also heavy traffic near Vicarage Road Cemetery.

A Herts Fire and Rescue Service spokesperson said: "Six fire engines, from Watford, Garston, Rickmansworth, Hemel Hempstead and Borehamwood were sent to the scene, where crews found a metal plating factory well alight.

"Firefighters tackled the fire with water and foam, made more complicated by the presence of chemicals used in the factory. Once the fire was contained and extinguished, the incident was scaled back across the morning, with the final fire engine leaving  the scene at around 11:30am. The fire is believed to have started accidentally."

The unit involved was Lamberts London Ltd.