Grunewald: Blast at bomb storage site sparks Berlin wildfire - BBC News
Firefighters could not get near the blaze due to sporadic explosions at the munitions facility.
Armoured police cars were brought in to try to safeguard the blast site

Explosions at an ammunition storage facility have caused a large wildfire in a forest in western Berlin.

The site in Grunewald forest is used by German police to store and detonate unexploded ordnance, often from World War Two, which continues to be dug up during construction.

Firefighters' efforts have been hampered by sporadic explosions which could be seen and heard miles away.

Questions are being asked about why the facility is in a forest prone to fires.

Some 140 firefighters are at the scene, and have set up a safety perimeter of 1,000m (3,280ft) because of the ongoing blasts.

"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," Berlin fire brigade spokesman Thomas Kirstein told reporters at the scene.

While the situation was "extremely extraordinary", he added, there was "no danger for Berliners".

An army tank has been sent in to evacuate munitions at the storage facility, which is run by Berlin police's weapons disposal units.

Remote-controlled de-mining robots and drones are also being used to help assess the situation, according to German media.

On Thursday afternoon, the blaze was still not under control and had burned 15,000 square metres of the forest, authorities said.

Munitions of all sizes are stored at the blast site, including fireworks. Videos shared online show how large some of the blasts were, and fireworks exploding in colour over the treetops.

This Twitter post cannot be displayed in your browser. Please enable Javascript or try a different browser. View original content on Twitter The BBC is not responsible for the content of external sites. Skip twitter post by rbb 88.8 This article contains content provided by Twitter. We ask for your permission before anything is loaded, as they may be using cookies and other technologies. You may want to read Twitter’s cookie policy, external and privacy policy, external before accepting. To view this content choose ‘accept and continue’. The BBC is not responsible for the content of external sites.

Firefighters are also battling a punishing heatwave, with Berlin forecast to hit 37C on Thursday. The forest is suffering from drought and is "bone dry", Jan Thomsen from the Department for Environment told Deutsche Welle radio station.

No firefighting helicopters were available to help, authorities said, because they were already busy in eastern Germany where there have been days of wildfires.

What caused the pre-dawn explosion that sparked the Grunewald forest fire is under investigation.