Some 400 firefighters and soldiers in the northeastern state of Mecklenburg-Western Pomerania battled against the largest wildfire in the region's history on Monday.

The blaze had affected some 430 hectares (1062 acres) of land around 50 kilometers (31 miles) southwest of the town of Schwerin by the early afternoon.

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The area was previously a military training site. State Environmental Minister Till Backhaus said emergency services were struggling to contain the fire because of unexploded munitions in the ground.

"The situation remains tense," said district official Stefan Sternberg. "At the moment, the priority is not extinguishing the fire, but securing nearby villages and keeping people safe."

Special vehicles and helicopters were helping firefighters, who were unable to get closer than a kilometer to the blaze because of the danger of further explosions.

Read more: German forest fires leap from 400 to 1,700 in a year

Concerns about WWII bombs

Mecklenburg's interior minister, Lorenz Caffier, said emergency services were doing all they could to protect a munitions warehouse that contained modern explosives and bombs dating back to World War II.

"We've taken every measure to secure it," he said.

Smoke reached the neighboring states of Brandenburg, Berlin and Saxony, prompting officials to tell residents to close their windows and doors. "The smell is annoying, but not dangerous," Berlin's fire service wrote on Twitter.

Sternberg said authorities had evacuated some 650 people from three towns and 100 children from a holiday camp near the fire overnight into Monday.

Emergency services believe the fire was started deliberately at three separate sites.

amp/rc (dpa, AFP)

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