A third member of the BASF fire brigade has succumbed to injuries sustained in the explosion and fire that hit the group’s Ludwigshafen complex on Oct. 17.  The death toll has now risen to four, including a crew member of a tank ship that was docked in the site’s North Harbor at the time of the blast. Seven other workers were seriously injured.

“All of BASF is in mourning,” CEO Kurt Bock said in a statement to announce the firefighter’s death. A memorial service for all of the victims was held on Oct. 30, and Ludwigshafen-based employees will observe a moment of silence at noon on Nov.2.

German state authorities are now beginning an investigation into the deadliest accident at BASF in decades, and Bock said last week the chemical giant will conduct its own independent investigation. As of Oct. 27, all but eight of the 20 plants that had been shut down immediately after the blast were back on stream. About a quarter of the facilities at the Ludwigshafen were operating below capacity due to feedstock delivery constraints, however.