The individuals were found later and checked by the police.
There were four people who had been running around and someone had observed them and perceived that one of the individuals had been holding some kind of weapon, says Martina Gradian, press spokesperson at the police.
It is about four people in their 20s and no weapon has been found. However, one of the individuals is suspected of minor narcotics offense.
The alarm came at 9:30 and the road into the nature reserve was blocked during the operation.
