Two Danish artists who have ridiculed Zimbabwe's Robert Mugabe and the Iraq war have turned their attention to Serbia's fugitive Ratko Mladic.
Pia Bertelsen (left) and Jan Egesborg carry out hotspot art
There is still support for Mr Mladic in Serbia, and nationalist groups recently plastered Belgrade with posters of him.
But most are now covered with little blue stickers that read: "We know where you are"; "We know when you have sex".
Artists Jan Egesborg and Pia Bertelsen, say their additions are a fun way of saying that Mr Mladic's time is up.
Ms Bertelsen says the stickers are a way of telling Mr Mladic that people like Nato and the Serb government know where he is.
Mr Mladic is wanted in connection with the massacre of nearly 8,000 Muslims at Srebrenica and the siege of Sarajevo in 1995.
But the actions of the artists, which they call "art in hotspots", has provoked different reactions on the streets of Belgrade.
"Reaction has been divided," says Ms Bertelsen, 32. "Half of the people say they think it is funny and brave and laugh about it - some asked us for stickers to give to their bosses.
"But we met a 19-year-old who says Mladic will never surrender and he is a Serbian hero.
"Another, who was in the Bosnian Serb army, said: 'Put up the stickers, but we will never let him surrender'."
The aim of their group "Surrend" is to invite tyrants and war crimes suspects to give themselves up, and to inject a little humour.
Mr Egesborg, 42, says they do not belong to any party or activist organisation.
Last year, he and another artists put up 1,000 ironic anti-war posters in Iraq - to get their message heard by ordinary Iraqi people.
The posters showed elephants, mice and cats together with messages like "Trust in Propaganda" and "Kill your Enemy".
He said they were in Belgrade for the funeral of Slobodan Milosevic and were struck by the lack of people demonstrating against him - or against Mr Mladic, who the Serbian government has promised to hand over to the UN war crimes court.
"I think we can make a difference in a positive way because it seems people in Serbia are quite depressed about the situation," he said. "We are hoping we can inspire people to get on the streets and protest like they did a few years ago."