A school in the German city of Hamburg was locked down for four hours by police after an "armed youth" was reported nearby.
Hamburg police said they launched a "major police operation" at the Otto Hahn School in the Jenfeld district on Tuesday.
A special units team searched the school premises for several hours but later gave an all-clear.
"Investigations on site are continuing," Hamburg police said on Twitter, "the pupils can now gradually leave the premises."
Authorities had earlier said it was unclear whether the reported gunman had actually entered the school building or just walked "in the direction of the school".
The Otto Hahn secondary school is named after the famous German chemist and is attended by around 1,500 students.
Tensions are running high in Germany after a gunman entered a university building in Heidelberg earlier this month, shooting one person dead and injuring three before turning the gun on himself.