Smoke described as smelly fog could be seen across a wide area after fire broke out at a chemical factory in Greenwich. Photo: Geoff Hill via Twitter

Around 60 firefighters tackled a huge blaze at a chemical processing plant in Greenwich, south-east London, this morning.

Smoke blasts into the early morning sky after a fire at a chemical processing plant in Grrenwich. Photo by Jon Henwood

Fire broke out at the factory in Peterboat Close, shortly before 3.30am.

Twelve crews were sent to the scene, off the approach to the Blackwall Tunnel.

Many people reported on Twitter hearing what they described as an “air-raid siren” going off that could be heard across the area.

Thick smoke could be seen for miles around.

A man who called himself Dave told BBC London that there was thick smoke on the Old Kent Road, a couple of miles to the west of the fire.

“You can’t see your hand in front of your face,” he said.

“It is like a smelly fog.”

Around half of the 80 x 40m industrial unit was alight in the blaze, which was under control by 6.50am.

Fire chiefs have advised people in the area to keep doors and windows closed as a precaution against the fumes.

Assistant commissioner Dany Cotton said: “Our firefighters worked extremely hard to contain the fire, which damaged around half of a big industrial unit.

“Heavy smoke spread throughout the area and as a precaution, we have asked people to keep their doors and windows closed.”

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