An investigation has been launched into the cause of a major blaze on the site of the former Onyx nightclub in Folkestone.

The fire at the seafront site started just after 9pm last night. Crews were still there this morning, damping down.

The club, affectionately known as the Priz, closed last year as plans proceed to develop Folkestone's harbour. Demolition work started at the site in February.

VIDEO: Firefighters tackle the blaze at the former Onyx nightclub.

A Kent Fire and Rescue Service spokesman said crews were faced with thick smoke coming from the main entrance of the former nightclub.

They warned people living near Marine Terrace to close windows and doors while they tackled the blaze. Motorists were advised to avoid the area.

Firefighters used breathing apparatus, six main jets and two water hydrants to tackle the blaze. The roof of the property was well alight.

VIDEO REPORT: Probe launched into fierce nightclub fire, Josie Hannet reports

No one has been injured and the cause of the fire is not yet known.

An investigation is being carried out today, and teams including forensics officers were at the scene this morning.

The road outside the building has been closed all day while investigations are carried out, Kent Highways said. It reopened at 2.30pm.

A spokesman for Kent Fire and Rescue said: "There is no indication yet as to the potential cause of the fire as an investigation is yet to commence."

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Reporter Sam Lennon, who was at the scene, said police sealed off a section of the area.

He said: "The roof was totally ablaze and the wind was blowing the smoke towards the harbour, causing passers-by to cough. The smoke totally blocked everybody's view.

"Firefighters were at the scene quickly and started putting out the fire."

Police, fire and ambulance crews were all called.

Guests at the nearby Grand Burstin Hotel said they became aware of the fire when they could smell the smoke.

Kevin Bransey said: "I could smell it coming through my window and I went outside to see what had happened. Then I saw the flames. The hotel did not have to be evacuated but we were moved to a safer part of the building."

Ernie Fuggle, who was manager of the Onyx building from 1976 to 1982, when it was the Pavilion Theatre, said: "I came here (the Burstin) for dinner and heard the smoke alarm go off and went outside to see what had happened.

"It broke my heart when they were going to demolish the building and it breaks my heart now that it's burning down.