Five people are missing and several people have been injured in an explosion on a chemical industrial park in Germany.

       Chempark operator Currenta said that the cause of the explosion at the site in the city of Leverkusen, about 13 miles north of Cologne, was unclear.

       Several staff were hurt, with at least two seriously injured, Currenta added.

       The explosion took place at a rubbish incineration plant, newspaper Daily Koelner Stadt-Anzeiger reported.

       Footage of the explosion on Tuesday shows a thick cloud of smoke rising out of the building that is on fire.

       The explosion has been classified as “an extreme threat” by Germany’s Federal Office for Civil Protection and Disaster Assistance.

       Several people have been injured, according to police in Cologne.

       They wrote on Facebook: “The situation in Leverkusen-Wiesdof is still confusing at the moment. We are on-site with many police forces and we are clarifying the situation. There are several injured people.”

       Residents have been asked to stay indoors with their windows and doors closed, German news agency dpa reported.

       The smoke cloud was moving in a north-western direction toward the towns of Burscheid and Leichlingen, Daily Koelner Stadt-Anzeiger reported.

       Emergency services had been deployed, and people from outside of Leverkusen have been advised to avoid the region.

       Several nearby motorways have also been shut.

       Recommended Tokyo Olympics: Moroccan boxer tries to bite ear of New Zealand opponent Lydia Jacoby: Video shows schoolmates going wild as 17-year-old US swimming prodigy wins surprise gold Fox News mocked for complaining about ‘inexcusable ambush’ of Tucker Carlson

       Leverkusen is home to Bayer, one of Germany’s biggest chemical companies. Many of the 163,000 residents of Leverkusen work at the pharmaceutical company.

       Additional reporting by AP