Turkish security officials raided the homes of two men in Turkey on December 30th, seizing a laptop containing details of a plan to attack Germany as well as Austria, Belgium, Britain, France and Turkey at the same time, Turkish officials told Hurriyet Daily News.
A group of 13 men planning to blow themselves up in suicide attacks left the northern Syrian province of Raqqa in accordance with the instructions found on the laptop.
The two men arrested in Turkey were the would-be suicide bombers tasked with the attack in that country.
Photos of potential targets around the capital city Ankara were found on the men's computers, including the courthouse, police HQ, a military school, mosques, shopping malls and two public squares.
Munich police issued a terror alert late on December 31st after Turkish intelligence shared the reports with German authorities.
Revellers were told to avoid large crowds and two main train stations in the Bavarian capital, which were both evacuated.
Large numbers of officers were deployed around the city in response to the threat, although celebrations mostly continued as normal.
Intelligence service believes threat still high
The Süddeutsche Zeitung and broadcasters Westdeutsche Rundfunk and Norddeutsche Rundfunk reported on Wednesday that Germany's foreign intelligence service (BND) remains on high alert for Islamic fundamentalist terror attacks.
The intelligence report seen by the media pointed to Isis' wide swath of territorial control and its powerful propaganda apparatus – which has successfully recruited "terror volunteers from the West outstripping all previously known numbers" – as particularly concerning.
Spies believe that despite ongoing airstrikes by Western nations, intensified following the attacks on Paris in November, that military action alone won't defeat Isis jihadism.
Thanks to support from Saudi Arabia and other Gulf states, jihadism has become "a socially relevant broad-based phenomenon", they wrote in the report.