"There was an explosion with several people injured for as-yet undetermined reasons at around 11:30 (local time) at BASF Ludwigshafen," it said in a press release.
"Emergency services from the whole region are on the scene to prevent the fire spreading to other parts of the plant," Ludwigshafen city authorities said in a statement.
The company said local residents should remain inside and shut doors and windows.
"We are still investigating the precise cause. The relevant authorities have been informed," BASF said.
Disclaimer: No Business Standard Journalist was involved in creation of this content