As German authorities brace for another possible attack, the popular Christmas market in Potsdam was evacuated after a suspicious package containing wires and electronics.
Meyritz wasn't immediately available to provide further details, but told the newspaper that the package measured about 40 centimeters by 50 centimeters (16 inches by 20 inches) and was apparently delivered by a messenger service.
The object was reportedly planted on a children's carousel located at the Christmas market, local media report.
Police confirmed the device was an IED, and evacuated the area. A follow-up police tweet clarified that no detonator was found. The suspect, Anis Amri, fled to Italy after the December 19 attack and died in a shootout with police near Milan on December 23, 2016.
Police have been on alert for any similar plots.
Germany has been on high alert since the incident last December.
But the Syrians were released without charge after initial investigations found there wasn't "sufficient evidence of a terror plot", the Frankfurt prosecutor's office said.
There's now no evidence showing they pledged allegiance to ISIS.
According to the initial account from police, the Syrian nationals had applied for asylum and were suspected of being ISIS members.
Christmas markets opened across Germany on Monday at the start of the holiday season, fortified with concrete barriers and security staff to protect shoppers. They'd also surveilled buildings in Berlin, the official alleged.