STORY: "We had explosion-like combustions and detonations. Debris was flying through the air, leading to a high danger to the life of the first responders, so they had to withdraw," said Thomas Kirstein.
According to the Berlin fire brigade, a forest area of more than 161 square feet was ablaze.
No injuries had been reported and residential areas had not been affected.
Police are blocking off an area with a radius of 0.62 miles around the detonation site. Public transport and roads around Berlin were affected.
Emergency personnel are damping down the surrounding forest areas.