Several hurt in blast at German chemical site

Two people were seriously injured Tuesday in an explosion at a chemical park in Leverkusen, western Germany, the site's operator said, as police urged residents to shelter indoors.

"Several employees were injured in the incident, at least two of them seriously," Chempark operator Currenta said in a statement. "Five employees are currently missing."

The blast happened at around 09:40 am (0740 GMT) "for still unknown reasons", it said.

The explosion could be heard far and wide and sent a thick column of black smoke into the air.

Germany's NINA warning app sent an "extreme danger" alert to residents, urging them to close all doors and windows and keep the emergency numbers free as much as possible.

Currenta said the incident occurred at Chempark's landfill and waste incineration area in Leverkusen's Buerrig district, which is separate from the main industrial park that houses numerous chemical companies including Bayer, Lanxess and Evonik Industries.

Currenta said firefighters and rescue crews were at the scene, as well as pollution detection experts.

Police in the nearby city of Cologne tweeted that they were closing several motorways in the Leverkusen area because of "major damage".

They urged drivers to steer clear of the area and told residents to move indoors "and close all windows and doors as a precaution".

"We are at the scene with many police officers to clarify the situation. There are several injured," police said.

Locals shared images on social media of the black cloud of smoke billowing into the air, with some saying their windows were rattled by the force of the explosion.