Berlin: A fire and an explosion in a World War II-era bunker injured at least 27 people early Tuesday in the northern German port city of Hamburg.
Firefighters said they would try to douse the blaze with foam to prevent the ignition of about 100 tons of essential oils stored in a carpentry workshop inside the bunker.
Several firefighters who rushed to the pre-dawn blaze were injured by the force of a blast strong enough to hurl debris and bicycles through the air.
"For now we won`t send anyone else into the building because the situation is unclear," a fire brigade spokesman told national news agency DPA.
"We plan to flood the bunker with foam to extinguish the fire."
Nine firefighters were among 11 people who suffered injuries, another firefighter collapsed, while 15 people were treated for smoke inhalation.
Officials said they were investigating the cause of the blaze in the concrete bunker in a residential area of the harbourside district of Rothenburgsort.
Hundreds of Nazi-era bunkers remain scattered across German cities, where they were often the only buildings to survive Allied bombing raids that destroyed surrounding neighbourhoods.
With their thick concrete walls, many bunkers proved too difficult to safely demolish after the war and city authorities opted to keep many of them to house businesses or as venues for cultural activities.