Fire service spokesman Sven Gerling said his initial information was that two helicopters had crashed, but he had no further details on the accident.
Federal Police spokesman Frank Brochert confirmed there "was an incident during an exercise" and that emergency crews were on the scene. He had no details about the accident.
More top news
Severe storms have ripped through the southern American state of Georgia leaving at least 11 dead and thousands without power.
So will our Prime Minister really be brave enough to challenge the new President's views on women and minorities?
Another bitterly cold day after a freezing, frosty morning, not much change this afternoon