Passers-by were confronted by a new addition to the statue commemorating the November Revolution of 1918 in Rostock, northern Germany, on Friday morning.
Someone had attached the flag of the outlawed PKK to the fist of the sailor statue. Firefighters were called immediately to remove it.
In Göttingen last week, police investigated Kurdish protesters for flying the flag of the PKK, whose symbols have appeared at Kurdish demonstrations across Germany.
The PKK, which is believed to have 13,000 supporters in Germany, has been banned in the country for many years in response to its armed struggle against Turkey.
In the early 90s the PKK attacked Turkish government buildings in Germany and in 1993 even stormed the Turkish Consulate in Munich.
As recently as 2012, Germany's parliament reaffirmed the ban on the PKK. The parliamentary state secretary for the interior ministry said at the time the PKK was a "destructive" force which undermined "peaceful co-existence" between Kurds and Turks in Germany.
In northern Iraq, German weapons and training are being delivered into the hands of the PKK's one-time Kurdish rivals, the peshmerga, but their fighters have not been able to put up the same level of resistance as the PKK and the two groups are increasingly working together.
It means arms the German government provides to the peshmerga could end up with a group classified as a terrorist organization by the EU.
But with a fighting force of 15,000, the PKK is Germany's and the West's best hope of staving off Isis advances and German Kurds are joining the fight, putting domestic security forces in a difficult position.
The gardening general
Around 50 Kurds are believed to have travelled from Germany to Syria and Iraq to fight against Isis, Spiegel magazine reported on Monday.
One such fighter is Shescho Khalaf, 61. A gardener in his home town of Bad Oeynhausen, North Rhine-Westphalia, he has become a general in Iraq.
Khalaf and his sons Abdul Karim and Haydar are leading the defence of Scherfedin, a city sacred to Kurdish Yazidi people on the Iraq-Syria border where thousands of civilians are surrounded by Isis forces.
“There are explosions and close-quarters fighting,” Seleman Khalaf, another of Shescho's sons who has remained in Germany, told Bild last week. “They desperately need help.”
Meanwhile, members of Kurdish biker gang Median Empire MC from Cologne have also travelled to Iraq.
This week they posted images of themselves with Kurdish Defence Minister Shex Jafar on Facebook, while members in Germany started a crowdfunding campaign to buy their comrades equipment.
While the Turkish government is allowing small numbers of Peshmerga fighters to travel through its territory to join the defence of Kobane, tensions remain high between the Ankara government and the Kurds.
Deputy PKK leader Cemil Bayik threatened a return to armed struggle earlier this month after Turkish security forces killed 31 people during protests in Kurdish areas of the country.
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