Germany explosion: At least two dead and others missing after huge blast at world's biggest chemical producer

Residents told to stay inside with windows closed as black smoke spreads from factory

At least two people have died and several remain missing after a huge explosion at a chemical factory in Germany.

Footage showed flames rising hundreds of feet into the air from BASF's headquarters in Ludwigshafen on Monday.

The fire was still burning five hours after the blast, when authorities confirmed the first death.

Firefighters try to extinguish fire at the factory of chemicals giant BASF in Ludwigshafen, Germany where several people had been injured following an explosion, October 17, 2016. (Reuters)

Uwe Liebelt, BASF's plant manager, said: "We deeply regret that employees have died and several have been injured. We extend our sympathy to those affected and their families."

Six workers suffered serious injuries and were taken to hospital for treatment, a spokesperson added, while two others remained missing. There were fears the death toll would rise as recovery work continued.

BASF said work on a pipeline was believed to be the cause of the blast at around 11.30am local time (10.30am BST).

"Work on a pipeline led to an explosion with secondary fires," a statement said. "Several people were injured. Several people are still missing."

The cause of the blast was under investigation as emergency services fought the flames, with German authorities informed of the apparent industrial accident.

Residents in the western cities of Ludwigshafen and neighbouring Mannheim were asked to remain inside and keep their doors and windows closed as black smoke spread from the blaze.

Children were also kept inside at nurseries and schools, with local residents reporting breathing difficulties according to the Rheinpfalz newspaper.

The chemical complex is the headquarters of BASF, the world's largest chemical producer, which employs 33,000 people at its factory in Ludwigshafen alone.

The company produces a wide range of industrial products, including solvents, glues, petrochemicals, plastics and fertiliser.

It has set up emergency phonelines for anyone concerned about the explosion, who were being asked to call 0800 5050 500.